Cosmic Background Explorer Guest Investigator Handbook Edition 2.1 General Sciences Corporation Applied Research Corporation Universities Space Research Association December 13, 1994 TABLE OF CONTENTS 1 OVERVIEW OF COBE 2 INTRODUCTION TO THE COBE GUEST INVESTIGATOR (GI) PROGRAM Table 2-1. COBE Guest Investigator Support Staff CONVENTIONS USED IN THIS HANDBOOK 3 DATA PROCESSING FACILITIES FOR GUEST USE 3.1 THE ULTRIX AND VAX/VMS WORKSTATIONS Figure 3-1. A VAX Session Manager window with Applications menu selected Figure 3-2. A typical DECterm window with $ DCL prompt 3.1.1 Automatic Start-up and Saving the Session Options 3.1.1.1 On the VMS Workstation 3.1.1.2 On the ULTRIX Workstation 3.1.2 Printing the Screen 3.1.2.1 On the VMS Workstation 3.1.2.2 On the ULTRIX Workstation 3.2 MACINTOSH 3.3 PRINTING AT THE CGIF 3.4 OFFLINE DATA INPUT/OUTPUT 3.4.1 Floppy Disks 3.4.2 Tape Drives 3.4.2.1 On the VMS Workstation 3.4.2.2 On the ULTRIX Workstation 3.4.3 CD ROMs 3.4.3.1 On the ULTRIX Workstation 3.4.3.2 On the Macintosh 3.5 DATA AND SOFTWARE AVAILABLE THROUGH NSSDC 3.6 ASTRONOMICAL DATABASES AT THE CGIF 4 COMPUTER ACCESS 4.1 USING X WINDOWS FROM A REMOTE SITE 4.2 COMMUNICATIONS 4.2.1 Modem 4.2.2 DECnet 4.2.2.1 To and from the VMS Workstation 4.2.2.2 From the ULTRIX Workstation 4.2.3 Telnet 4.2.3.1 To and from the VMS Workstation 4.2.3.2 To and from the ULTRIX Workstation 4.2.3.3 From the Macintosh 4.3 ELECTRONIC MAIL 4.3.1 On the VMS Workstation 4.3.2 On the ULTRIX Workstation 4.4 FILE TRANSFER 4.4.1 COPY (VMS Workstation) 4.4.2 DCP (ULTRIX Workstation) 4.4.3 FTP 4.5 EXAMPLE: REMOTE CONNECTION 4.6 EXAMPLE: READING A CD ROM ON CUBA FROM ZWICKY 5 PROJECT DATA SET OVERVIEW 5.1 DATA FORMATS AVAILABLE 5.2 DIRBE PROJECT DATA SETS 5.2.1 DIRBE Product Description 5.2.2 DIRBE Data Records 5.2.3 DIRBE Data Quality Summary 5.3 DMR PROJECT DATA SETS 5.3.1 DMR Product Description 5.3.2 DMR Data Records 5.3.3 DMR Data Quality Summary 5.4 FIRAS PROJECT DATA SETS 5.4.1 FIRAS Product Description 5.4.2 FIRAS Data Record 5.4.3 FIRAS Data Quality Summary 6 CGIS SOFTWARE OVERVIEW 6.1 THE CGIS EXECUTIVE 6.2 UIMAGE 6.3 UIDL 6.4 ADDITIONAL ANALYSIS PACKAGES 6.4.1 IRAF 6.4.1.1 On the VMS Workstation 6.4.1.2 On the ULTRIX Workstation 6.4.1.3 Getting Help in IRAF 6.4.2 AIPS 6.4.2.1 On the ULTRIX Workstation 6.4.2.2 Getting Help in AIPS 6.4.3 SAOimage 6.5 PROGRAMMING LANGUAGE COMPILERS 6.5.1 FORTRAN 6.5.1.1 On the VMS Machines 6.5.1.2 On the ULTRIX Workstation 6.5.2 C 6.5.2.1 On the VMS Workstation 6.5.2.2 On the ULTRIX Workstation 6.6 WORD PROCESSING PACKAGES 6.6.1 TeX and LaTeX on the VMS Workstation 6.6.2 TeX and LaTeX on the ULTRIX Workstation 6.6.3 Microsoft Word on the Macintosh 7 OTHER PRINTED RESOURCES 7.1 PROPOSER INFORMATION PACKAGE 7.2 EXPLANATORY SUPPLEMENTS 7.3 COBE GUEST INVESTIGATOR HANDBOOK 7.4 CGIS SOFTWARE USER'S GUIDE 7.5 COBE SOFTWARE CATALOG 7.6 LIBRARIES AVAILABLE TO GUEST INVESTIGATORS APPENDIX A VISITING THE CGIF Figure A-1. Schematic of the Washington metropolitan area, showing airports and major highways Figure A-2. Schematic of the Washington Metro routes Figure A-3. Map of hotels and restaurants near Goddard Figure A-4. Layout of the Goddard Space Flight Center APPENDIX B ACRONYMS USED IN THIS MANUAL APPENDIX C THE COBE SKYCUBE AND PROJECTION EQUATIONS Figure C-1. COBE skycube, ecliptic coordinates Figure C-2. COBE skycube, galactic coordinates Figure C-3. COBE skycube, resolution 6 pixel numbering Figure C-4. COBE skycube, resolution 9 pixel numbering APPENDIX D NETWORK ADDRESSES INDEX =============================================================================== 1 OVERVIEW OF COBE Since the discovery in 1964 of the Cosmic Microwave Background (CMB), interpreted as relic radiation from the Big Bang, scientists have tried to make accurate measurements of its spectrum and anisotropies. With the launch of COBE on November 18, 1989, major advances in our understanding of the very early universe have been achieved. COBE was constructed and operated by the Goddard Space Flight Center. Essential to meeting the scientific objectives were an all-sky observing strategy, periodic absolute calibrations of the instruments, high sensitivity, and extensive care in the experimental design to minimize potential systematic errors. COBE carried three scientific instruments to achieve its objectives: the Far Infrared Absolute Spectrophotometer (FIRAS), the Differential Microwave Radiometers (DMR), and the Diffuse Infrared Background Experiment (DIRBE). Both the FIRAS and the DIRBE were located inside a liquid helium cryostat that maintained a thermal environment of 1.5 K while the helium lasted. The DMR receivers were located around the outside of the cryostat. The objective of the FIRAS was to measure the spectrum of the CMB over the wavelength range 0.1 to 10 mm, with an accuracy of 0.1% of the peak brightness. This instrument, a Michelson interferometer, had a spectral resolution of 0.2 cm^(-1) (6 GHz) and an angular resolution of 7 degrees. It measured small deviations in the shape of the CMB spectrum from that of a blackbody. The DMR searched for spatial anisotropies at 31.5, 53, and 90 GHz using 2.6 degree pixels on the sky. These frequencies were selected to allow separation of the CMB signature from galactic synchrotron emission, free-free emission, and emission by interstellar dust in the data analysis process. There were two independent channels at each frequency. The DIRBE was designed to search for the cosmic infrared background resulting from the cumulative emissions of the first galaxies and stars. The DIRBE objectives were to discern and measure the spectrum and angular distribution of this diffuse infrared background radiation to a sensitivity of 10^(-13) W/cm^2/sr, or 1% of the total background, whichever is greater, in 10 photometric bands from 1 to 300 micrometers. The instrument had a field of view of 0.7 degrees. DIRBE also measured linear polarization in the 1 to 3 micrometer channels to help distinguish astronomical foregrounds from the extragalactic components of the measured intensities. COBE was launched into a 99 degree inclination, 900 km altitude circular orbit with a 6 PM ascending node. With this orientation, the spin axis of the satellite was always pointed away from the Earth and about 94 degrees away from the Sun. The orbital period was approximately 103 minutes. The satellite rotated at 0.8 rpm. This rotation helped reduce potential systematic errors in the DMR and provided DIRBE a range of solar elongation angles from which to view scattering and emission from interplanetary dust. The cryostat cover was ejected three days after the COBE launch, and all three instruments began obtaining sky data. During the first month in orbit, various spacecraft maneuvers were undertaken to test the performance of the instruments and spacecraft, and to optimize instrument parameters. During this entire period the instruments were obtaining high quality data. All three instruments had completed their full sky coverage by mid-June 1990 and continued with a second survey. On September 21, 1990, the 600 liters of liquid helium were depleted, ending over 10 months of cryogenic operation for FIRAS and DIRBE. After helium depletion, the FIRAS was turned off, since this instrument required operating at liquid helium temperatures; it had surveyed the sky 1.6 times. The DMR continued to operate normally in all of its six channels until the data taking was ended in December 1993. Two years after launch, the noise levels in the resulting sky maps were steadily decreasing, showing that the sensitivity limits of this instrument had not been reached. Following helium depletion, the four short wavelength bands of DIRBE continue working remarkably well, but the DIRBE long wavelength bands were turned off because of the diminished data quality at elevated temperatures. This continuation of data taking by these two instruments is expected to be important in further understanding any systematic errors and for complete closure on the sky as the Earth completes its annual cycle around the Sun. In particular, the interplanetary cloud in which we reside must be understood well enough to model and remove it from the data in order to search for a cosmic infrared background. COBE has obtained several major cosmological results. FIRAS confirmed the Big Bang model's prediction that the CMB would have a thermal spectrum. Data analyzed by January 1993 showed no deviation from a perfect blackbody spectrum to 0.03% of the peak intensity. The temperature of the universe was found to be 2.726 +/- 0.010 K, and it was found to be almost equally bright in all directions. The FIRAS instrument has also made the first all-sky infrared spectral line survey, in addition to mapping the spectra of the galactic dust distribution at wavelengths greater than 100 micrometers. Nine lines from interstellar [C I], [C II], [N II], and CO have all been clearly detected, and [C II] at 158 micrometers and [N II] at 205.3 micrometers have sufficient intensity to be mapped. These global data help us to understand the heating and cooling mechanisms in our galaxy. The DMR experiment has obtained the most precise maps of the CMB anisotropy ever made. The observed anisotropy in CMB brightness on angular scales of about 10 degrees is of order (Delta T)/T ~ 10^(-5). This result supports standard dark matter scenarios of structure formation and inflation in the early universe, although the ruling out of more complex theories will have to await experiments with smaller angular resolution. COBE has also obtained with DIRBE the most extensive infrared absolute sky brightness measurements and maps ever made, providing spectacular new views of the Milky Way Galaxy and permitting the search for cumulative light from the first objects in the universe. Spectra indicate that the faintest levels of emissions from our solar system and galaxy occur at wavelengths of 3.4, 140, and 240 micrometers. Careful modelling of these foreground emissions are now in progress, and the detection of the infrared cosmological background, or stringent limits, will be obtained. 2 INTRODUCTION TO THE COBE GUEST INVESTIGATOR (GI) PROGRAM The data analysis facilities for the Cosmic Background Explorer (COBE) guest investigator program are located at the COBE Guest Investigator Facility (CGIF) at the NASA/Goddard Space Flight Center in Greenbelt, Maryland. Many of the principal investigators, deputy principal investigators, and Science Working Group members are resident at Goddard, which also houses a technical library. Most of the science support staff are located at the Cosmology Data Analysis Center (CDAC), one mile from Goddard. Upon arrival at the CGIF, the guest investigator will work with a support scientist, who will be familiar with the guest's proposal and will be available during the guest's visits to help with technical information. Table 2-1 gives the names, phone numbers, and addresses of the guest investigator support staff. =============================================================================== Table 2-1. COBE Guest Investigator Support Staff For... Name Location Phone ------ ---- -------- ----- User Support Dave Leisawitz GSFC 26/140A 286-0807 CGIF SPOC Jeffrey Newmark CDAC 120 513-7788 DIRBE Data Information Janet Weiland CDAC 150 513-7809 DMR Data Information Chuck Bennett GSFC 21/158 286-3902 FIRAS Data Information Joel Gales CDAC 120 513-7763 Systems Management Jon Stokes CDAC 135 513-7804 Documentation Gayle Rawley CDAC 120 513-7764 ============================================================================= CONVENTIONS USED IN THIS HANDBOOK There are several typographical conventions used in this document: * The RETURN or ENTER key is indicated by . * The left, center, and right workstation mouse buttons are , , and , respectively, unless otherwise defined by the user. * The CONTROL key is shown by a carat: ^. The user must keep the control key depressed while typing the following key stroke. * The names of software menu items and file names are in bolded fixed- width (typewriter) font. * Examples show the computer display in bolded fixed-width font, with literal USER'S ENTRIES in standard fixed-width font for clarity. User entries that are not meant to be taken as literal input, such as username, are shown in an italicized proportional-width font. Note that although the user's entries are usually shown in upper case letters, VMS is not case-sensitive; capital letters are used for better readability. Users are warned in the text where letter case is an issue (i.e., UNIX and IRAF). For example, in the command line Local> C node_name the Local> prompt is put on the screen by the computer. The user enters C and a specific node name (ZWICKY, for instance). * In the examples, we will show the system level prompts as follows: $ VMS % ULTRIX 3 DATA PROCESSING FACILITIES FOR GUEST USE This chapter describes the data processing facilities available to guest investigators. Availability and accessibility of software packages is discussed in Chapter 6. 3.1 THE ULTRIX AND VAX/VMS WORKSTATIONS The node name of the DECstation 5000/200 ULTRIX workstation is CUBA, and the node name of the VAXstation 4000/60 VMS workstation is ZWICKY; they are both located in the COBE Guest Investigator Facility (CGIF), Building 21, Room C129 at the Goddard Space Flight Center. The VMS workstation is a high-resolution, full- color display terminal capable of supporting imaging as well as basic plotting functions. It has 1280 x 1024 pixel resolution and supports 8-bit color. Because the workstation is running under Motif, the largest IDL display window is 1258 x 978. The ULTRIX workstation has the same imaging capability and resolution as the VAXstation, but it has 24-bit color instead of 8. Working at the workstation consoles requires some familiarity with the DECwindows system running Motif, but for those users who are inexperienced, online help menus are found at the right of almost every menu line. A few general notes on using the mouse with the windows are listed below. * The default labels for the mouse buttons are 1 through 3 from left to right and are commonly expressed as , , and in help screens and the CGIS Software User's Guide. * Clicking means pushing down a mouse button (usually the left one) and releasing it (unless otherwise instructed). * Double-clicking means clicking twice in rapid succession. * Dragging is accomplished by pressing and holding the mouse button down while moving the mouse pointer to the desired location. * The menu line is the line in the window just below the title. Menu choices may be seen by pressing and holding the mouse button on the menu item. To make a selection, drag the pointer down until a box appears around the desired selection, then release the button. If none of the selections are to be chosen, simply moving the pointer out of the menu allows a safe exit. * The right hand side of most windows features a scroll bar with an up arrow above and a down arrow below. These control what text is seen in the window. To see previous items that have scrolled up out of the window, click on the fat part of the bar and drag it up a little. Release the button and the text will update. Clicking on the arrows lets you move up and down one line at a time. To begin your session, enter your username and password. After a short while, a small window labeled Session Manager appears on the screen (see figure 3-1). A DECterm window should appear shortly after, displaying some login messages and then the system prompt (see figure 3-2). If it does not, start up a DECterm window by clicking on the Application menu in the Session Manager window and selecting DECterm. +-----+------------------------------------+-----+ |+----+-------------------------------+----+----+| ++ -- | Session Manager on ZWICKY | o | O ++ |+----+-------------------------------+----+----+| || +------------+ || ++ Session |Applications| Options Help ++ || +------------+--------+ || |+----+----+Bookreader ...+---------+----+| +-----+----+CDA Viewer ...+---------+-----+ |Calculator ...| |Calendar ...| |Cardfiler ...| |Clock ...| |DECsound ...| |DECterm ...| |FileView | |LinkWorks Manager ...| |Mail ...| |Message Window | |Notepad ...| |PCA | |Paint ...| |Print Screen ...| +---------------------+ Figure 3-1. A VAX Session Manager window with Applications menu selected. +-----+---------------------------------------+-----+ |+----+----------------------------------+----+----+| ++ -- | DECterm 1 | o | O ++ |+----+----------------------------------+----+----+| || || ++ File Edit Commands Options Print Help ++ |+-------------------------------------------------+| || $ || |+----+---------------------------------------+----+| +-----+---------------------------------------+-----+ Figure 3-2. A typical DECterm window with $ DCL prompt. At this point in a session, the DECterm window behaves just like an ordinary terminal on the machine. When a session is complete, the standard logout (LO on VMS and logout on ULTRIX) will close and remove the DECterm window. Choosing Quit from the Session menu of the Session Manager ends the workstation session completely. The default font for DECterm windows is a small font that some users may find difficult to read. To change the window font to a larger font, choose Options from the VMS DECterm menu line or Customize from the ULTRIX DECterm menu line. Now choose Window... and click on the button next to Big font. Click on Apply to see if the result is suitable; if so, click on OK. To make this font size the default for all subsequent VMS DECterms, choose Options again from the VMS DECterm menu and now select Save options. To make this font size the default for all subsequent ULTRIX DECterms, choose Customize again from the ULTRIX DECterm menu and now select Save Current Settings. 3.1.1 Automatic Start-up and Saving the Session Options 3.1.1.1 On the VMS Workstation To have a DECterm or anything else (e.g., a clock or calendar) brought up automatically at the beginning of a VMS session, first choose Options from the DECterm menu line. Now select Automatic Startup... from the VAX Session Manager. Click on the items in the left list that you would like to have started at the beginning of each session. When you have finished your selections, click on the OK box. Once you have selected the applications, choose Options from the Session Manager. Select Save Session Manager. The next time that you begin a session, these applications will be started automatically. 3.1.1.2 On the ULTRIX Workstation To have a DECterm or anything else (e.g., a clock or calendar) brought up automatically at the beginning of a ULTRIX session, first choose Customize from the ULTRIX DECterm menu. Now select Autostart from the pull-down menu. Click on the items in the left box that you would like to have started at the beginning of each session, then click on OK. To keep these settings for future sessions, choose Customize from the DECterm menu line. Then select Save Current Settings. The next time that you begin a session, these applications will be started automatically. 3.1.2 Printing the Screen 3.1.2.1 On the VMS Workstation It is possible to capture a portion of the workstation screen for printing. To do this on ZWICKY, click on the Applications option on the Session Manager window. From this menu, choose the Print Screen... option. Soon a Print Screen window will appear. Then choose the appropriate options. Change most options by pressing on the diamonds to the left of the option. An option is set when the diamond is darkened. Be sure that PostScript is marked under the Output Type. Give the output file a name by first clicking in the box labeled Output File Name and then typing in a file name. Once all of the options have been set, click on Print Screen in the Print Screen window menu. Print Portion of Screen, Print Entire Screen, Capture Portion of Screen, and Capture Entire Screen are available. Because of the current configuration of the printers, you must use one of the capture options. To write the entire screen to a file, click on Capture Entire Screen, and the screen will be written into the specified PostScript file. To get only a portion of the screen, click on Capture Portion of Screen. The workstation pointer turns into a large red plus (+) sign. Move the marker to one corner of the region to be captured. Press and hold down , drag the mouse to stretch the box around the entire region, and then release . The region inside the box will be written to the previously specified file name. (This may take a few minutes.) To close the Print Screen window, click on File in the window menu and then choose Exit. Send your file to the appropriate printer (see section 3.3 for print queues). 3.1.2.2 On the ULTRIX Workstation To print the entire screen or a portion of it on CUBA, first click on the Customize option on the Session Manager window. From this menu, choose the Print Screen... option. A Customize Print Screen window appears, and in it there are several options to mark appropriately. Change most options by pressing on the squares to the left of the options. An option is set when the square is darkened. Be sure that PostScript is marked under the Output Format. Give the output file a name by first clicking in the box labeled Output File Name and then typing in a file name. Once all of the options have been set, click on the OK button in the window. To print the screen or a portion of it, click on the Print Screen option on the Session Manager menu line. Print Portion of Screen, Print Entire Screen, Capture Portion of Screen, and Capture Entire Screen are available. To print the entire screen, click on Print Entire Screen. A Queue Options window appears. Check and mark all of the options, including choosing a printer in the Printer box (see section 3.3 for print queues). When you are finished, click on OK, and the screen will be sent to the specified printer and to the file specified in the Queue Options box. To print a portion of the screen to a file, click on Print Portion of Screen. The workstation pointer turns into a large red plus (+) sign. Move the marker to one corner of the region to be captured. Press and hold down , drag the mouse to stretch the box around the entire region, and then release . The region inside the box will be sent to the previously specified printer. (This may take a few minutes.) Capturing all of the screen to a file is similar to printing all of the screen, except that you are also presented with a Screen Dump Destination window in which you may change the name of the file in which the screen capture is stored. Capturing a portion of the screen is similar to printing a portion of the screen, but the Screen Dump Destination window appears before the screen region to be printed is selected. 3.2 MACINTOSH One Macintosh Centris 650 is available for guest investigator use and is also located at the CGIF. Manuals for many of the applications are kept on the desk to the left of the Mac keyboard. We ask that you do NOT remove any of this documentation from the CGIF area, as we cannot replace it. We assume here that you are familiar with Macintoshes, so here we define only some of the terms we shall be using later: * Clicking means pushing down the mouse button and releasing it. * Double-clicking means clicking twice in rapid succession. * Dragging is accomplished by pressing and holding the mouse button down while moving the mouse pointer to the desired location. * The menu line is the line at the top of the window just below the title. Menu choices may be seen by pressing and holding the mouse button on the menu item. To make a selection, drag the pointer down until the desired selection is highlighted, then release the button. If none of the selections are to be chosen, simply move the pointer out of the menu. * The right hand side of most windows features a scroll box with an up arrow above and a down arrow below. These control what text is seen in the window. To see previous items that have scrolled off of the window, click on the box and drag it up a little. Release the button and the text will update. Clicking on the arrows lets you move up and down one line at a time. Using MacX The MacX software package has been installed on the guest machine, allowing you to use the Mac as an X Window display. At this time, only service to the CUBA (ULTRIX) workstation (or other UNIX-type workstation) is operational. To start the package, double-click on the icon for the hard disk in the upper right corner of the desktop. Open the MacX Application folder. Double-click on MacX. When MacX is running, you will see that the choices in the top menu line have changed. Go to the Remote menu and choose New Command. The resulting New Remote Command window has several boxes for you to complete. Start with Remote Command by clicking in the box. Enter the following command: /usr/bin/X11/xterm -ls -title "(R)host xterm" -sb -display "(R)display" You can make the (R) symbol by holding down the OPTION key and pressing the letter r. Fill in the rest of the boxes as indicated below: Command Name any name by which to identify your session Display (0) Color Rootless (The box is really a menu.) Output Save Username your username on CUBA Password your password on CUBA Execute at Startup click in the box; an X will appear there Click on Host; this will open a whole new window. Choose MacTCP Tool from the Method menu. Enter cuba.gsfc.nasa.gov (or desired node name) in the Host Name box. Press , which will close the Host window and return you to the New Remote Command window. Finally, click on Execute. If everything is working correctly, an xterm window will appear, with a prompt indicating that you are already logged onto the host computer. When you have completed your session, log out of the host computer. If you have just completed your first MacX session, you will probably want to save your session setup for future use. To do this, go to the File menu and choose Save As. Enter a name for your setup file; it will appear in the MacX Application folder. Then click on Save. Choose Quit to close the application. The next time you want to start a MacX session to the same computer, just double- click on your entry, not on the MacX icon. You will be prompted for your password on the remote host. Once that is entered, click on OK, and your session should start automatically. In general, X Window terminals make use of a three-button mouse, rather than a one-button Macintosh mouse. Mappings between the X system and the Macintosh are as follows: X terminal Macintosh equivalent mouse button left arrow right arrow CONTROL clover key META up arrow arrow keys hold down OPTION key and press arrow keys You can find more detailed information in the Apple MacX binder near the machine; see especially the User's Guide, Chapter 2: Getting Started. 3.3 PRINTING AT THE CGIF The CGIF laser printer is an HP LaserJet 4M, located near the main door to Room C129. It handles both ASCII and PostScript formats. Print files from the workstations using the commands $ PRINT/QUEUE=CGIF$LASER filename (VMS) and % lpr -Pcgiflaser filename (ULTRIX) Color PostScript files may be printed on the Tektronix Phaser IISD in the International Ultraviolet Explorer (IUE) Regional Data Analysis Facility (RDAF) in Room G33 of Building 21. The corresponding print commands are $ PRINT/QUEUE=TEKSD filename (VMS) and % lpr -Pstars_teksd filename (ULTRIX) We offer several notes on color printing: * Tektronix prints are expensive; please use them sparingly. * You should check that the printer is loaded with the correct paper tray before sending your file. Examine the print queues with the commands $ SHOW QUEUE/ALL queue_name (VMS) and % lpq -Pqueue_name (ULTRIX) Removing a job from a print queue requires the job entry number, displayed by the command $ SHOW QUEUE queue_name (VMS) or % lpq -Pqueue_name (ULTRIX) Print jobs may then be deleted with $ DELETE/ENTRY=entry_number (VMS) or % lprm -Pqueue_name job_number (ULTRIX) (This may not be working yet.) To set up printing from the Macintosh, go into the apple menu in the left corner and choose Chooser. A Chooser window appears. Click on Laserjet 4M in the panel in the upper left. Click on !Goddard Backbone from the list in the lower left. Click on LASP Laserjet 4Si from the list on the right, then click on OK. This printer is located in Room G33, next to the Tektronix color printer. 3.4 OFFLINE DATA INPUT/OUTPUT The table below gives a quick summary of the external devices available on each machine. Explicit direction on using these drives are given in the following sections. +-----------+---------------------------------------+ | CUBA | CD ROM, 4mm tape, 3 1/2" floppy | +-----------+---------------------------------------+ | ZWICKY | 4mm tape | +-----------+---------------------------------------+ | MAC | CD ROM, 3 1/2" floppy | +-----------+---------------------------------------+ The following list gives product sizes for those users planning to copy software or data: Product Approximate size(Mb) ------- -------------------- UIMAGE/UIDL software 1 DIRBE, 10 photometry channels, 6 +/- 10 degrees galactic latitude DMR, 1 channel, all-sky 0.3 FIRAS, Left High Fast scan mode, 3 +/- 15 degrees galactic latitude 3.4.1 Floppy Disks The ULTRIX workstation CUBA is equipped with a 3 1/2" disk drive that uses 1.44 Mb PC floppies. Access to this disk drive is currently limited to superusers. The Macintosh uses 3 1/2" floppies (double sided, high density) which have 1.44 Mb capacity. Note that the 3 1/2" Macintosh disks may NOT be used in CUBA. 3.4.2 Tape Drives Both the VMS workstation ZWICKY and the ULTRIX workstation CUBA are equipped with 4mm tape drives. Some fundamental operations are discussed in the following sections. 3.4.2.1 On the VMS Workstation VMS 4mm tapes may be one of two kinds: a backup tape or a copy. The use of backup tapes only is described here. Listing Contents of a Backup Tape --------------------------------- To begin, insert the tape into the ZWICKY tape drive. (An arrow on the top side of the tape indicates which way to insert the tape.) Now type $ MOUNT/FOREIGN ZWICKY$MKA500: to mount the tape onto ZWICKY's tape drive whose device name is ZWICKY$MKA500:. If all goes well, you should see this message with the tape's label name in place of labelname: %MOUNT-I-MOUNTED, LABELNAME mounted on _ZWICKY$MKA500: To list everything that is currently on the tape, type $ BACKUP/LIST/REWIND ZWICKY$MKA500: This will list all of the files on the tape. (The /REWIND qualifier assures that the tape is rewound before the contents are listed.) Creating a Backup Tape ---------------------- To create a backup tape, begin by inserting the tape into the tape drive. (An arrow on the top side of the tape indicates which way to insert the tape.) Now type $ INITIALIZE ZWICKY$MKA500: labelname and type in a label for your tape which can be up to 6 characters long. Now mount the tape: $ MOUNT/FOREIGN ZWICKY$MKA500: To back up user Smith's entire account on ZWICKY, enter $ BACKUP/LOG ZWICKY$DKA400:[SMITH...]*.*;* _To: ZWICKY$MKA500:saveset_name/LABEL=labelname where labelname is the same labelname that was specified at the initialization step, saveset_name is the name of the backup save set, and ZWICKY$DKA400: is the device name for the disk serving all guest users on ZWICKY. The /LOG qualifier causes the filenames to be displayed as they are being written to the tape. It may be handy to have a list of the contents of your tape to serve as a printed record. To write such a list to a file, execute this command: $ BACKUP/LIST=filename/REWIND ZWICKY$MKA500: If you do not specify an extension for the filename, i.e., .TXT or .DAT, the extension will be .LIS. To copy specific files from the tape to the disk, use the command $ BACKUP/LOG/REWIND ZWICKY$MKA500:/SELECT=filename ZWICKY$DKA400:[dirname] Dismounting a Tape ------------------ To dismount a 4mm tape from ZWICKY, type $ DISMOUNT/NOUNLOAD ZWICKY$MKA500: Omit the /NOUNLOAD qualifier if you would like the tape to be ejected. If you use the plain DISMOUNT command, the tape will be ejected automatically after a short pause. 3.4.2.2 On the ULTRIX Workstation To read or write to a 4mm tape on CUBA, first insert the tape into the drive labeled /dev/rmt0 in the direction indicated by the arrows on the top of the tape. Because the system default device is defined to be the device on CUBA, it will not be specified in the following command examples. The tape drive writes at high density by default. To produce a listing of the files on the tape, use the command % tar tv To save a file onto the end of the tape, type % tar rv filename To produce a listing of tar options, type % tar H To create a new archive at the beginning of a tape, use % tar cv filename_to_read To extract a file from the tape and place it in the current directory, use the command % tar xv filename_on_tape Push the button to the right of the tape drive to eject the tape. These are only a few of many functions available with the tar command. To view a complete list of the command's options, type man tar at the UNIX prompt to access the help file. 3.4.3 CD ROMs Much computer system information and many astronomical databases are now available on CD ROM (compact disc, read only memory). CD ROM players are attached to both the CUBA DECstation and the Macintosh. =============================================================================== WARNING Before loading a CD ROM into ANY machine, it MUST be placed into a caddy. Caddies are generally kept in or near the CD drive; contact a systems management staff member if a caddy is missing. =============================================================================== 3.4.3.1 On the ULTRIX Workstation The CD ROM player on CUBA is an RRD42 drive. The caddy for this type is opened by pressing the corner tabs as indicated on the caddy and lifting the lid. Insert the CD ROM with the label facing up, then close the caddy lid. Press the corners firmly. Pushing the loaded caddy into the drive loads the CD. Once the CD ROM is physically loaded, it must be mounted on the system: % mountcd (UNIX file systems) You should get a message back saying that the CD has been mounted on directory /cdrom; if you do not, try the following command: % mnt9660cd (all other ISO 9660 format) Once the CD is mounted, you can treat it like any other read-only directory. Note: If the files on the CD are in VMS format, e.g., README.TXT;1, you will need to use single quotes around the file name: % cp 'README.TXT;1' cuba_c/giusers/your_dir/readme.txt When you have finished, you must dismount the CD, first making sure that your working directory isn't pointing to the disk: % unmountcd BEFORE EJECTING THE CADDY, THE DISC MUST BE DISMOUNTED. The CD is unloaded by pushing the disc eject button on the right side of the player, just below the disc slot. 3.4.3.2 On the Macintosh The CD caddy for the Macintosh is usually stored in the overhead shelf to the left of the Mac keyboard and display. (The manuals for the CD ROM drive are also kept here.) Begin by inserting your CD into the caddy. DO NOT INSERT THE CD DIRECTLY INTO THE DRIVE! To open the caddy, press in the corner tabs as indicated on the caddy and lift the lid. Insert the CD ROM with the label facing up, then close the caddy lid. Press the corners firmly. Insert the caddy into the built-in drive in the unit to the right of the keyboard. After a few seconds, an icon with the name of your CD will appear below the icon of the hard disk in the upper right corner of the desktop. You access files on the CD as you would files on the hard drive. To retrieve your CD when you have finished, drag the icon of the CD into the Trash icon. (This sounds terrible, but really will not harm your CD.) The caddy will automatically eject. 3.5 DATA AND SOFTWARE AVAILABLE THROUGHNSSDC The National Space Science Data Center (NSSDC) provides access to many data sets that may be of interest to COBE guest investigators, including COBE data. These are disseminated through the NODIS (NSSDC's On-line Data Information Services) account, accessed from the guest investigator machines with a SPAN address of NSSDCA (node number 15.188 or integer 15548) or Internet address NSSDCA.GSFC.NASA.GOV (node number 128.183.36.23). The user name for the account is NODIS; there is no password. Six service categories are available through NODIS: * Multi-disciplinary, including NSSDC online data (COBE and others), the Master Directory (describes and sets up links to remote data systems), CD ROMs available from NSSDC, requests for offline data, and the NSSDC Newsletter * Astrophysics, including the Astronomical Data Center catalogs and FITS * Space Physics, including the Space Physics Data System, Geophysical Models, and Near-Earth Heliosphere data (OMNI) * Planetary sciences * Earth sciences * Life sciences/microgravity 3.6 ASTRONOMICAL DATABASES AT THE CGIF A subset of the COBE Project Data Sets is available locally on both the CUBA and ZWICKY workstations. On ZWICKY (VMS), the data are stored in the ADBDISK:[PDS_FITS] directory; the logical CGIS_FITS points to the same area. On CUBA (ULTRIX), the data are stored in the /cuba_b/cgis/data/pds_fits directory, which can also be accessed by the logical $CGIS_FITS. Additional astronomical databases (ADBs) are available at the CGIF on ZWICKY. The main directory is ADBDISK:[ADB]; this and all subdirectories contain files called AAA_README.TXT that explain the directory contents. Two subdirectories are of particular interest to guest investigators: * ARCHIVE contains external data sets that have been converted to COBE skymap form. * RAW contains the external data sets in their native formats. The contents of the ADB directories as of May 18, 1994 are given in the table below; an online version of the list is found in the file ADBDISK:[ADB.RAW]AAA_DIR.LIS. Subdirectory in ADBDISK:[ADB.RAW]Astronomical Database 3CR 3rd Cambridge Revised Catalog 4C 4th Cambridge Catalog ABELL_ZWICKY Abell and Zwicky catalogs of clusters of galaxies AFGL Air Force Geophysics Lab Infrared Sky Survey BRIGHT_STARS Yale-SAO Bright Star Catalog CLAS Combined List of Astronomical Sources CO_CLEMENS Massachusetts-Stony Brook CO survey of the first galactic quadrant. CONDON1400MHZ Condon-Broderick 1400 MHz Sky Survey CONDON_4850MHZ Condon, Broderick, Seielstad 4.85 GHz Sky Survey COSB COS-B FITS map DEARBORN Dearborn Observatory catalog of faint red stars DIRBE_TIP DIRBE Test Initial Product DMR_TIP DMR Test Initial Product FIRAS_TIP FIRAS Test Initial Product GEZARI Gezari "Catalog of Infrared Observations" GREENBANK_87GB * Greenbank "87GB" 4.85 GHz Source List GREEN_SNR Green Supernova Remnant list HASLAM408MHZ * Haslam 408 MHz Sky Survey HAYNES5GHZ Parkes 5 GHz maps (Haynes, et al.) HCO_CFA_REDSHIFT Center for Astrophysics Redshift Catalogs HEILES_HABING_H1 Heiles and Habing HI (21cm) Sky Survey IRAS_ALLSKY IRAS All-sky maps IRAS_2JY_Z IRAS 2 Jansky redshift survey IRAS_GAL_CTS IRAS Galaxy Counts IRAS_PS IRAS Point Source Catalog IRAS_SMALL_SCALE_STR IRAS Small Scale Structure Catalog IRAS_SSF_12 IRAS Super Sky Flux plates at 12 micrometers IRAS_SSF_25 IRAS Super Sky Flux plates at 25 micrometers IRAS_SSF_60 IRAS Super Sky Flux plates at 60 micrometers IRAS_SSF_100 IRAS Super Sky Flux plates at 100 micrometers IR_CROSS_INDEX "Infrared Source Cross-Index" by Schmitz KUEHR5GHZ_STRONG_SOURCE 5 GHz Strong Sources by Kuehr, et al. LOCKMAN_H1 * Lockman HI data LUBIN_SMOOT_90GHZ Berkeley 90 GHz balloon survey MERCG Merged Catalog of Galaxies, including IC, UGC, de Vaucoulers, MCG, Zwicky NEUGEBAUER_TMSS The Neugebauer Two Micron Sky Survey PARKES_H1_UMD Parkes HI line survey from Kerr, et al., U. of Maryland PARKES_CAT90 The Parkes Catalog of Radio Sources, version 1.01 PRINCETON_25GHZ Princeton 25 GHz balloon survey REDDENING Burnstein-Heiles reddening maps REICH1420MHZ * Reich and Reich 1420 MHz Sky Survey RESTRICTED_MIT_PRINCETON_19GHZ MIT-Princeton 19 GHz balloon survey RICH_GAL_CLUSTERS Abell Catalog of rich clusters of galaxies SAS2 SAS2 catalog of galaxies, pulsars, and other sources SHAP_AMES Revised Shapley-Ames catalog of bright galaxies SHARPLESS_H2 * Sharpless HII Source List STARK_HI Bell Labs/Stark HI sky survey UGC Uppsala General Catalog (included in MerCG) WEAVER_WILLIAMS_H1_UMD * Weaver and Williams HI Line Survey from University of Maryland tape -- has even 1 km/sec grid WEAVER_WILLIAMS_H1_ADC * Weaver and Williams HI Line Survey from Astronomical Data Center (ADC) WHITE_BECKER_1400MHZ_NORTH 1.4 GHz Northern Sky Catalog of White and Becker WISC_SOFT_X Wisconsin soft x-ray data and maps ZIP Zodiacal Infrared Project data base * Available in COBE skymap form 4 COMPUTER ACCESS Guest users are given an account on the GI computer of their choice (see chapter 3 for available platforms). The account comes equipped with an appropriate login file (e.g., LOGIN.COM file on the VMS workstation), which the user may further customize. 4.1 USING X WINDOWS FROM A REMOTE SITE You may access the GI workstation remotely using DECnet or Telnet. Running image processing software (e.g., UIMAGE) from your remote workstation requires the several additional steps given below. (Image processing over a modem line is extremely slow and not recommended.) Before logging in to the guest investigator machine, you must set up your local session to allow it to be used as a remote X Window display. Exactly how you do this depends upon the platform you are using. * From a VAXstation, choose Options from the Session Manager window menu, then choose Security.... Enter the full node name of the GI machine, e.g.., ZWICKY.GSFC.NASA.GOV. It is usually sufficient to enter * for the username. Enter DECNET or TCPIP as appropriate for transport. Then click on Add. The new entry should appear under Authorized Users. Click on OK when you have finished. * From a DECstation, choose Customize from the Session Manager window menu, then choose Security.... If the remote node you are trying to reach is not on the Authorized Hosts list, click in the blank Host Name box and enter the full node name. Then click on Add; the authorized list should now contain the new node. Click on OK when you have finished. * From a Sun or other X Window workstation running under UNIX, you should enter the following command at your local system prompt: % xhost +gi_node_address e.g., % xhost +zwicky.gsfc.nasa.gov Now log into the guest investigator workstation of your choice. Before invoking any imaging software, type $ SET DISPLAY/CREATE/NODE=your_full_home_node_address/TRANSPORT=xxx (VMS) where xxx is DECNET (if you connected using a SET HOST) or TCPIP (if you connected using TELNET), or % setenv DISPLAY your_full_home_node_address:0.0 (ULTRIX) Now your local X Windows terminal should behave like the workstation console. Note to ULTRIX users: Certain software packages check more than the DISPLAY environment variable to identify the terminal type. IDL, for example, uses the IDL_DEVICE variable (set it to x), while AIPS uses TERM (use xterm). 4.2 COMMUNICATIONS 4.2.1 Modem The VMS and ULTRIX machines are accessible by dial-in modem at both 2400 [(301)286-9000] and 9600 baud [(301)286-4000]. The 2400 baud modem lines also support 1200 baud communications. The standard parameters are 8 bits, no parity, and 1 stop bit. Once you are connected, you will see the following prompt, which you should answer as shown: ENTER NUMBER: LASP You should then see CALLING 59721 (or some other number) CALL COMPLETE Respond by typing . You should now get several lines of terminal server messages, followed by a prompt. Respond as shown: Local> C CGIS (to connect to ZWICKY) or Local> telnet cuba (to connect to CUBA) When you have logged out of your host session, you will be returned to the server: Local> LO and then break your modem connection. 4.2.2 DECnet 4.2.2.1 To and from the VMS Workstation To access another machine on DECnet from the VMS workstation, type $ SET HOST node_name For example, to reach the On-Line Data Information Services node at the National Space Science Data Center, type $ SET HOST NSSDCA If our system does not recognize the node name, you may have to provide the integer node address instead. This is typically a 4 or 5 digit number, and is used in place of the node name, as in this example for an alternate way of reaching NSSDC: $ SET HOST 15548 Some tables of addresses provide a decimal number, such as 15.188 for NSSDCA above, instead of an integer. You compute the integer value by multiplying the units digit by 1024 and then adding the number after the decimal point. Thus, 6.29 becomes 6 x 1024 + 29 = 6173. Your DECnet session is ended and control is returned to your original session when you log out of your remote session. If your system does not recognize the ZWICKY node name, the DECnet numbers are 15.851 and 16211. 4.2.2.2 From the ULTRIX Workstation The DECstation may be used to access remote nodes via DECnet using the dlogin command. At the ULTRIX system prompt, type % dlogin node_name_or_number On this system, the node number may be either the integer or the decimal form of the address. You can access a local command shell by typing ~. This shell allows you to log your session to a file, suspend it, etc., as explained in its internal help. To exit the local shell, type alone. As with the VMS workstation, the DECnet session ends when you log out of the remote session. Alternate ways to terminate the dlogin process are possible using the local command mode. 4.2.3 Telnet 4.2.3.1 To and from the VMS Workstation The VMS machine will also allow you to attach to remote nodes using Telnet. You may specify either a node name or number. For example, the Internet address for a node at the NSSDC is 128.183.36.23. This machine can therefore be reached by either $ TELNET NSSDCA.GSFC.NASA.GOV or $ TELNET 128.183.36.23 Telnet connections are closed when you end your remote session, or they can be broken from the VMS workstation by typing ^Z. The full Telnet addresses for the VMS workstation are ZWICKY.GSFC.NASA.GOV and 128.183.87.26. 4.2.3.2 To and from the ULTRIX Workstation Telnet connections from the ULTRIX workstation are made in the same way as for the VMS machine. Telnet connections are broken when you exit your remote session. Alternatively, typing ^] gives you a telnet> prompt; typing ? at the prompt gives you a list of commands, including close to close the connection. The full Telnet addresses for the ULTRIX workstation are cuba.gsfc.nasa.gov and 128.183.87.27. 4.2.3.3 From the Macintosh To start Telnet from the Macintosh, open the icon for the hard disk in the upper right corner of the desktop. Double-click on the Telnet 2.6 folder. (Note: There are some bugs with Telnet version 2.6; version 2.5 is also available on the guest Macintosh.) Start the program by double-clicking on the NCSA Telnet 2.6 icon. Choose Open Connection from the File menu. Click on the arrow to the right of the Host/Session box, and select the machine to which you want to connect. Click on Connect. This version is equipped with Tektronix 4105 emulation. 4.3 ELECTRONIC MAIL 4.3.1 On the VMS Workstation The GI VAXstation supports the VAX MAIL facility. You can find online information about MAIL by typing $ HELP MAIL Additional (and more detailed) information is available by asking for help within MAIL: $ MAIL MAIL> HELP MAIL may be used to communicate with any users with SPAN or Internet access. The protocol for addressees on SPAN is node_name::userid CDAC personnel have accounts on the COBECL cluster; their user names are typically their last names. To reach the documentation support person, for example, use the electronic address COBECL::RAWLEY. Many of the COBE group members working at the Goddard Space Flight Center also have accounts on the STARS cluster; thus the project scientist can be reached at STARS::MATHER. In some instances the destination cluster for your message may not be recognized by the GI VAXstation, especially if it is located somewhere other than GSFC. There are several ways around this. One workaround is to use the STARS VAX at GSFC as an intermediate node, i.e., use the protocol STARS::node_name::userid. This will also work for incoming mail; if the outside cluster does not recognize the GI VAXstation node, try STARS::ZWICKY::userid Another alternative is to use the equivalent cluster number nnnnn, as in 7120::RAWLEY. (See section 4.2.2.1 for more information on DECnet addressing.) The address protocol for Internet users is SMTP%"user_id@internet_or_arpanet_address" (Note: Double quotes rather than single quotes are required.) For example, if someone's network address is SMITH@ABC.DEF.GHI, you would address your mail message to SMTP%"SMITH@ABC.DEF.GHI" Please note: Do NOT address Internet mail for COBECL users to COBECL.GSFC.NASA.GOV; this is not a valid address, and the message will be lost. Instead, use the form username@cobecl.dnet.nasa.gov or username@CDAC_node_name.gsfc.nasa.gov You can also send messages to users on GSFCMAIL, NASAMAIL, and TELEMAIL. The protocol is similar to that above, with the address specified as SMTP%"user_id@mail_type.nasa.gov" e.g., SMTP%"SMITH@GSFCMAIL.NASA.GOV" Send messages to BITnet users with the address SMTP%"user@host.bitnet" You receive BITnet mail at the address user@zwicky.dnet.nasa.gov 4.3.2 On the ULTRIX Workstation The GI DECstation supports the UNIX mail facility. You can find online information about mail by typing % man mail A list of commands is available by asking for help within mail: % mail & help Note that you can only get help this way if you have unread mail messages. mail may be used to communicate with users at the CDAC, the GSFC VAX clusters, and at any other facility with SPAN access. The protocol for the addressee is the same in either case: % mail node_name::userid CDAC personnel have accounts on the node COBECL; their user names are typically their last names. To reach the documentation support person, for example, use the electronic address COBECL::RAWLEY. Many of the COBE group members working at the Goddard Space Flight Center also have accounts on the STARS cluster; thus the project scientist can be reached at STARS::MATHER. In some instances the destination cluster for your message may not be recognized by the GI workstation, especially if it is located somewhere other than GSFC. There are several ways around this. One workaround is to use the STARS VAX at GSFC as an intermediate node, i.e., use the protocol STARS::node_name::userid. This will also work for incoming mail; if the outside cluster does not recognize the GI workstation node, try STARS::CUBA::userid Another alternative is to use the equivalent cluster number nnnnn, as in 7120::RAWLEY. (See section 4.2.2.1 for more information on DECnet addressing.) mail can also be used to send electronic mail to users on Internet or Arpanet. The address protocol within mail is simply % mail user_id@internet_or_arpanet_address For example, if someone's network address is SMITH@ABC.DEF.GHI, you would send your message as % mail smith@abc.def.ghi Please note: Do NOT address Internet mail for COBECL users to COBECL.GSFC.NASA.GOV; this is not a valid address, so the message will be lost. Instead, use the form username@cobecl.dnet.nasa.gov or username@CDAC_node_name.gsfc.nasa.gov You can also use mail to send messages to users on GSFCMAIL, NASAMAIL, and TELEMAIL. The protocol is similar to that above, with the address specified as % mail user_id@mail_type.nasa.gov e.g., % mail smith@gsfcmail.nasa.gov Send messages to BITnet users with the address format user@host.bitnet You receive BITnet mail at the address user@cuba.dnet.nasa.gov 4.4 FILE TRANSFER 4.4.1 COPY (VMS Workstation) The DCL COPY command can be used both for local file transfers (between directories on the GI VAXstation) and for transfers to and from the VAXstation to other machines using either the VMS or ULTRIX operating system. COPY supports all file types, including text, binary, and executable images. Local file transfers from one user area to another require only that you have read access to the source file and write access to the destination directory. Use the standard DCL COPY syntax: $ COPY source_disk:[source_directory]source_file destination_file where the file destination is assumed to be your current default directory. If this is not the case, the destination file specification will also require the directory and (if not on your disk) the disk identifier. You can also use the COPY command to copy files to and from your home DEC installation to the VAXstation if appropriate security arrangements have been made (e.g., a proxy has been set up). If the source files have world read access, you just have to add the remote VAX node name to the source file specification: $ COPY source_node::source_disk:[source_directory]source_file - _$ destination_file (The - is the VMS continuation character; VMS also provides the continuation prompt _$.) If the source files do not have world read access, you must provide information to the remote system to authorize access to the files (assuming your ID account on the remote system has read privileges for the source files). (Because this involves displaying your password, we encourage you to use FTP, described in section 4.4.3, for this type of transfer if the remote node is also on the Internet.) If you must use COPY, you can use this generic call: $ COPY s_node"s_user s_password"::s_disk:[s_dir]s_file d_file For example, $ COPY EREWHON"MORE UTOPIA"::THEDISK:[TOM]PARADISE.TXT - _$ THE.END will copy the file PARADISE.TXT from the directory THEDISK:[TOM] to the user MORE (password UTOPIA) on the node EREWHON to the local directory, under the name THE.END. If you wish to split up some of the typing, or want to copy more than one file, you may define a logical symbol for the remote node that includes the source node, user's ID, and password. This is done using the DCL ASSIGN command as follows: $ ASSIGN "remote_node""userid password""::" NODE (The ASSIGN may be extended to include the disk name and directory; insert them between the last colon and the last double quote mark. You may also use the DCL command DEFINE; see the online system help for the correct syntax and examples.) Now use COPY as before, this time using the symbol NODE in place of the actual remote node name: $ COPY NODE::source_disk:[source_directory] source_file - _$ destination_file if the source file is at the remote VAX. The NODE symbol can also be used to copy files to a remote VAX, assuming that the user's ID at the remote installation has write access to the destination directory. There are some caveats in any file transfer between installations. If there is a large distance between machines, you may want to use the /READ_CHECK qualifier for the DCL COPY. This will read each record twice in order to catch transmission errors. Also, the speed of file transmission depends both upon the speed of the line between the installation and the usage of the machines at each end. Transferring files larger than a few thousand blocks may be very slow during prime computing hours, so we advise you to transfer large files during off-hours whenever possible. You may wish to check the transmission speed with a small file before starting to copy large ones. 4.4.2 DCP (ULTRIX Workstation) The dcp command is the ULTRIX equivalent of the VMS COPY command, allowing you to copy files between any two machines connected by DECnet. To copy from a VAX node to the ULTRIX workstation, use the syntax % dcp vax_node::'vax_disk:[vax_dir]vax_file' ultrix_file For example, the transfer of the file TESTING.123 from VAX node EARTH, disk MISSION, directory CONTROL to an ULTRIX file of the same name is done with the command % dcp earth::'mission:[control]testing.123' . where that final . indicates that the same filename should be used. Writing into a directory requires the password for the account: % dcp ultrix_file \ % vax_node/vax_user_name/vax_password::'vax_disk:[vax_dir]vax_file' If, for example, you want to write into the sample file above, you would use the command % dcp test.roger earth/control/moon::'mission:[control]\ % testing.123' (The \ is the ULTRIX continuation character.) More information on using dcp is available by typing man dcp at the ULTRIX system-level prompt. As for DECnet COPY, if you do not wish to display your password, you may want to try FTP instead. 4.4.3 FTP FTP (File Transfer Protocol) can be used for transferring files between the VMS and ULTRIX workstations and remote Internet nodes. The commands shown in the following examples are for the VAXstation; corresponding commands for each platform appear in a table at the end of this section. We use $ to indicate the local system prompt and FTP> for the prompt within FTP. To connect to a remote site, type $ FTP Internet_node_name The system may respond with an FTP prompt, at which you enter: FTP> USER user_name_on_remote_machine You will then be prompted for the corresponding password. A confirmation of login appears if all is well. For example, user SMITH might see something like FTP> USER SMITH GET remote_file_name local_file_name If you do not specify the local file name, it will have the same name (or its closest translation) as the version on the remote machine. File and directory names must adhere to the conventions of the machine on which they reside. (UNIX operating systems are case-sensitive and define directories with /, for example.) To transfer multiple files from the remote site to the local site, use the MGET command. FTP> MGET JUNK.* The * acts as a wildcard. In the above example, all files in the current directory of the remote node with the name JUNK and any extension (JUNK.TXT, JUNK.DAT, etc.) will be copied into the current local directory with the same names they had on the remote machine. To transfer a file from the local site to the remote, FTP> PUT local_file_name remote_file_name There is also an MPUT command for transferring several files at once. GET and PUT may also be entered without file names; the systems will respond with at least minimal prompting for the names, depending on the platform. To change directories at the remote site, type FTP> CD directory_name or enter CD alone, and you will be prompted for the directory name. Change your local site directory with the command FTP> LCD directory_name To see a listing of the remote site file directory, type DIR. A listing of the local site directory can be seen by typing LDIR. Other local VMS commands may be issued by typing PUSH; when finished, LO returns the session to FTP at the remote site. A list of valid commands may be obtained at any time by typing ? with no at the FTP prompt. Type HELP command for a short description of any listed command. To end the remote session, type FTP> BYE to disconnect from the remote session, then FTP> QUIT to return to the local session. In general, you must have complete login information (user name and password) for the remote site in order to do file transfers with FTP. However, many hosts make available an anonymous FTP service. To use this service, log on in the usual way with the user name anonymous and an arbitrary password. Network etiquette demands that you use your e-mail address or at least your user ID as a password. This service, when available, usually does not gain access to all files on the host, but only to those that the host system administrator makes available for anonymous FTP. Here is a table of the corresponding FTP commands for each of the operating systems: +----------------------------+--------------------+------------+ | Action | VMS | ULTRIX | +----------------------------+--------------------+------------+ | Log in | USER, LOGIN | user | +----------------------------+--------------------+------------+ | Get remote file | GET, RECEIVE | get, recv | +----------------------------+--------------------+------------+ | Get multiple remote files | MGET, MULTIPLE GET | mget | +----------------------------+--------------------+------------+ | Send a file | PUT, SEND | put, send | +----------------------------+--------------------+------------+ | Send multiple files | MPUT, MULTIPLE PUT | mput | +----------------------------+--------------------+------------+ | Change remote directory | CD, CPATH | cd | +----------------------------+--------------------+------------+ | Change local directory | LCD, LOCAL-CD | lcd | +----------------------------+--------------------+------------+ | List remote directory | DIR, LS(*) | dir, ls(*) | +----------------------------+--------------------+------------+ | List local directory | LDIR, | !ls | | | LOCAL-DIRECTORY | | +----------------------------+--------------------+------------+ | Other local commands | PUSH, SPAWN | !(**) | +----------------------------+--------------------+------------+ | FTP command listing | ? | ? | +----------------------------+--------------------+------------+ | FTP command description | HELP | help | +----------------------------+--------------------+------------+ | Interactive prompting for | CONFIRM | prompt | | MGET, MPUT | | | +----------------------------+--------------------+------------+ | Set file type for binary | BINARY, TYPE IMAGE | binary, | | files | | image | +----------------------------+--------------------+------------+ | Disconnect from remote FTP | BYE, CLOSE | close | | server | | | +----------------------------+--------------------+------------+ | Terminate FTP session | QUIT, EXIT | bye, quit | +----------------------------+--------------------+------------+ * File names only ** Type exit to return to FTP 4.5 EXAMPLE: REMOTE CONNECTION The following example shows a remote user on a UNIX workstation how to set up their home node to run COBE image processing software, start a CGIS analysis session, and transport files for local printing. In the example, the UNIX workstation on which Jo User is working is called SPACE.UNIV.EDU, and ZWICKY.GSFC.NASA.GOV is the GI node to which Jo User will connect. In the example, we use this font for computer prompts and replies, this font for your keyboard entries, and [this font] for our side comments. Menu choices are presented like this: Menu title: Select this item: +--------------------------+-------------------------+ | Title of menu | Choice from menu | +--------------------------+-------------------------+ [Click on the menu to make the selection.] You will also see the following prompts: $ when you are at the VMS system level (DCL) % when you are at the UNIX system level means to press the RETURN key ON YOUR HOME NODE % xhost +zwicky.gsfc.nasa.gov [Add the GI node to your authorization list.] % telnet zwicky.gsfc.nasa.gov [Log in to the GI machine.] ON THE GI NODE $ SET DISPLAY/CREATE/NODE=SPACE.UNIV.EDU/ - $ TRANSPORT=TCPIP [Send any displays to your home node (space.univ.edu). Note that the dash (-) is the VMS continuation character.] $ CGIS [Begin a CGIS analysis session.] Jo User has now successfully initiated a session with the CGIS software. (See the CGIS Software User's Guide for detailed information on the CGIS Executive, UIMAGE, and UIDL.) Within this session, Jo User created a PostScript image to copy home for printing: Menu title: Select this item: +-------------------+-------------------------------+ | CGIS Main Menu | Shell to Operating System | +-------------------+-------------------------------+ [Go to VMS.] $ FTP SPACE.UNIV.EDU [Begin FTP transfer.] ZWICKY.GSFC.NASA.GOV MultiNet FTP user process 3.0(102) Connection opened (Assuming 8-bit connections) USER JoUser [Use your username here.] PUT ZWICKY.PS To remote file: HOME.PS [Put the PostScript file ZWICKY.PS into the SPACE file HOME.PS.] SPACE.UNIV.EDU> QUIT [Quit the FTP session.] $ LOGOUT [Log out of the spawned VMS session and return to the CGIS Main Menu.] 4.6 EXAMPLE: READING A CD ROM ON CUBA FROMZWICKY This step-by-step example illustrates the process of reading a CD ROM mounted on the CUBA workstation. $ TELNET CUBA [Connect to the ULTRIX workstation.] Trying... Connected to CUBA.GSFC.NASA.GOV : [access warnings] : login: jouser Password: Sec$ret [Login as usual; password is not echoed.] : login messages : [Insert the CD ROM into the caddy (see section 3.4.3). Insert the caddy into the CD ROM drive on CUBA.] % mountcd Mounting CD-ROM on directory /cdrom [Mount the CD (UNIX file system).] % cd /cdrom /cdrom [Change the default directory to the CD top-level directory.] % ls readme/ [List the files.] % cd readme /cdrom/readme [Change to the readme subdirectory.] % ls junk1.txt junk2.txt junk3.ps % ftp zwicky [Now connect back to ZWICKY.] Connected to zwicky.gsfc.nasa.gov : [login messages] : Name(zwicky:jouser): [acknowledgement of username] Password: MORESEC$RET [acknowledgement of login] [Log in to ZWICKY.] ftp> put junk1.txt [Transfers junk1.txt to your ZWICKY login directory.] ftp> quit [End the FTP session.] % cd ~jouser [You must move off of the CD ROM to dismount it.] % unmountcd Unmounting CD-ROM from directory /cdrom [Eject the CD from the drive, and remove the disc from the caddy.] % logout [Leave CUBA and return to your original ZWICKY session.] 4.7 MOSAIC Mosaic is a point-and-click interface that makes obtaining information from the Internet relatively painless. It allows, among other things, the display and downloading of text, images, and data, and gives you access to the World Wide Web (WWW). A pared-down version of mosaic (no sound or movie player) is running on both the CUBA and ZWICKY workstations. To spawn off a mosaic session, type % mosaic & Do not be alarmed by the warning messages about missing fonts. The NCSA home page should appear. Any text in blue, underlined type has been linked to further information; clicking on the word allows you to access these additional topics. You can reach other sites over the Internet if you know their corresponding Uniform Resource Locator (URL) addresses. To enter a URL, click in the Open box at the bottom of the window; this opens an Open Document window. Place the cursor in the URL to Open box, and move the cursor pointer around until a small I-beam cursor appears on the line. Enter your new URL. If you make a mistake, use the mouse to highlight the offending text, then type in the correct characters. The backspace and delete keys do not work. Click in the Open box to open the connection to the new remote site. Below are some URLs that you may find useful: COBE home page http://www.gsfc.nasa.gov/astro/cobe/cobe_home.html Astrophysics Data System (ADS) Abstract Service http://adswww.harvard.edu/abs_doc/abstract_service.html Astronomy Conferences http://cadc.dao.nrc.ca/meetings/meetings.html NASA home page http://hypatia.gsfc.nasa.gov/NASA_homepage.html WebStars: Astrophysics on the Web http://guinan.gsfc.nasa.gov/WebStars.html GNN (Global Net Navigator) Directory http://192.190.21.10/gnn/GNNhome.html EINet Galaxy (net by topics) http://galaxy.einet.net/galaxy.html Planet Earth home page http://white.nosc.mil/info_modern.html Digital (DEC) FTP and WWW Archives http://gatekeeper.dec.com Gopher server gopher://wiretap.spies.com/11/Etext Note that these addresses are subject to change. Click in the Back or Forward boxes at the bottom of the window to revisit sites at any time during your session without the need to re-enter the URL. To end your session, click on the File item in the menu across the top of the mosaic window, and choose Exit program. Then click on Yes in the exit confirmation window that appears next. 5 PROJECT DATA SET OVERVIEW More complete information about data format and quality is available in the Proposer Information Package or in the Explanatory Supplement for each instrument. Hardcopies are available from the documentation support contact. Online versions of the Proposer Information Package and the Explanatory Supplements are available by anonymous FTP from the NSSDC under [COBE.PROJECT_DATA_SETS]. Each Explanatory Supplement, when available, will be stored in the directory containing the corresponding data. You can scroll through the text of the Proposer Information Package using the CGIS Main Menu, Documentation branch. 5.1 DATA FORMATS AVAILABLE The Project Data Sets are available in time-ordered data files and FITS binary tables (COBE skymaps). Guest investigators at the CGIF will have access to the files as well as the CGIS software for working with the skymaps. The software is equipped with a user-friendly interface that allows you to read in the COBE data sets quickly and to begin their analysis. The UIMAGE and UIDL packages were written specifically to handle the COBE skymap projection and provide several important analysis tools particular to COBE data analysis, including various model fitting, imaging, and plotting routines. 5.2 DIRBE PROJECT DATA SETS 5.2.1 DIRBE Product Description The DIRBE Project Data Sets consist of: 1) absolutely calibrated time-ordered data (8 GB) 2) a set of 41 weekly-averaged sky maps (2.5 GB) 3) maps at fixed solar elongation (angle between the line-of-sight and the Sun) of 90 degrees (0.13 MB) 4) annual-averaged sky maps (0.24 MB) 5) Galactic plane maps (0.04 MB) 6) beam profiles (small) 7) system spectral response function (ASCII - small) 8) color correction tables (ASCII - small) The time-ordered data are binned into 32 second time intervals (1 Major Frame, MF) containing 10240 Bytes. Each MF includes the output from the 16 IR detectors (three each in bands 1-3 and one in all other bands), detector parameter settings, operating status and environment flags, outputs from all engineering sensors, attitude information, and selected data from the other instruments and the spacecraft. Each MF contains 256 samples of each detector's output, one for each 1/8th second (four chopper cycles). The time-ordered IR sensor data are exactly those used as the basis to construct the weekly-averaged maps. All sky map Project Data Sets are presented in the COBE map format which divides the sky into pixels of approximately 0.32 degrees x 0.32 degrees in size. The pixel locations are a fixed grid and each data sample is assigned to the center of the nearest pixel. Information provided for each pixel includes the pixel number, the sky brightness at each wavelength, the standard deviations of the mean values, the number of effective observations, the mean solar elongation angle, and time for the averaged observation, and ancillary data. In addition, at 1.25, 2.2, and 3.5 um, the three detectors at each of these wavelengths measure the total intensity and orthogonal linearly polarized components of the signal. From these we have derived Stokes parameters Q and U, and these are also included for each pixel in the weekly-averaged maps. It should be noted that when creating the sky maps, data taken when the Moon is within 10 degrees of the line-of-sight (LOS) are excised. In addition, data following a Moon transit, which heavily saturates all of the detectors, are removed using different time cuts for different bands (30 seconds for all bands except the 12 - 100 um bands, which have 3 minutes of data removed). Data are also removed if a planet or bright comet or a bright asteroid is near the LOS. All such data remain in the time-ordered data set. 5.2.2 DIRBE Data Records Data fields (Time-Ordered Calibrated Intensities File): ------------------------------------------------------- Time Attitude Photometry for 16 detectors (MJy/sr) Standard deviations of photometric values (MJy/sr) Engineering sensors (data numbers) Ancillary information includes the approach vector and a South Atlantic Anomaly (SAA) flag. Data fields (Weekly-Averaged Sky Map Files): -------------------------------------------- DIRBE pixel number (resolution 9) Sub-pixel containing the mean line-of-sight Sub-pixel number of the average line-of-sight (bands 1A, 4, 7, 8) Average time of observation Difference between the average time of observation for each photometric band and the average time of all observations of the pixel Mean solar elongation angle Photometry for 10 full-intensity bands (MJy/sr) Stokes' parameters Q and U for the polarization channels Number of observations of the pixel for week Sum of the applied observation weights for 10 photometric bands Standard deviations for the full-intensity bands (MJy/sr) Standard deviations for the Stokes' parameters Q and U Solar system objects flag Fraction of data used Quality flag for polarization ratios in Stokes' parameters Ancillary information includes ecliptic and Galactic coordinates of the pixel center. Data fields (Annual-Averaged Sky Map Files): -------------------------------------------- DIRBE pixel number (resolution 9) Sub-pixel containing the mean line-of-sight Average time of observation Photometry for full-intensity bands (MJy/sr) Standard deviations for the full-intensity bands (MJy/sr) Sum of the applied observation weights for photometric bands Sum of the total number of observations available Data fields (Elongation 90 degrees Sky Map File): ------------------------------------------------- DIRBE pixel number (resolution 9) Time corresponding to observation of pixel at solar elongation = 90 degrees Photometry for full-intensity bands (MJy/sr) Effective number of observations of the pixel over the mission Standard deviations for the full-intensity bands (MJy/sr) Fit quality flag Fit chi^2 per degree of freedom Ancillary information includes ecliptic and Galactic coordinates of the pixel center. Data fields (Galactic Plane Sky Map Files): ------------------------------------------- DIRBE pixel number (resolution 9) Photometry for full-intensity bands (MJy/sr) Data quality flag - contains both quality flag and standard deviation Time corresponding to observation of pixel Ecliptic longitude Ecliptic latitude Galactic longitude Galactic latitude 5.2.3 DIRBE Data Quality Summary Effective Pixel noise Minimum Spectral Wavelength bandwidth* (5 sigma) pt. source band (microns) (Hz) (MJy/sr) (Jy) -------- ---------- ---------- ------------ ---------- 1 1.25 5.94e+13 0.1 30 2 2.2 2.28e+13 0.1 30 3 3.5 2.10e+13 0.1 30 4 4.9 8.61e+12 0.1 30 5 12 1.16e+13 0.6 170 6 25 4.41e+12 0.8 220 7 60 2.26e+12 1.3 360 8 100 1.15e+12 1.4 390 9 140 6.13e+11 40 11,200 10 240 4.99e+11 20 5,600 * Assumes source spectrum nu*I(nu) = constant 5.3 DMR PROJECT DATA SETS 5.3.1 DMR Product Description The purpose of the Differential Microwave Radiometers (DMR) experiment is to measure large angular scale anisotropies of the cosmic microwave background (CMB) radiation. This release of the DMR Project Data Sets covers the first two years of instrument operation, specifically the time range from 1989 December 22 to 1991 December 21. The DMR Project Data Sets are (i) maps of the full sky at three microwave frequencies, (ii) the corresponding differential data sorted by sky position to provide sky sampling information, and (iii) the time-ordered raw differential temperatures. Smoot et al. (1990) and Bennett et al. (1992) provide detailed descriptions of the DMR instrument. The DMR experiment consists of six differential microwave radiometers, two nearly independent channels (labelled A and B) at each of three frequencies: 31.5, 53, and 90 GHz (wavelengths 9.5, 5.7, and 3.3 mm). Each radiometer measures the difference in power, expressed as a differential antenna temperature, between two regions of the sky separated by 60 degrees. The combined motions of spacecraft spin (75 s period), orbit (103 m period) and orbital precession (~1 degree/day) allow each sky position to be compared to all others through a highly redundant set of all possible difference measurements spaced 60 degrees apart. The DMR has three separate receiver boxes, one for each frequency, that are mounted 120 degrees apart on the outside of the cryostat containing the Far Infrared Absolute Spectrophotometer (FIRAS) and the Diffuse Infrared Background Experiment (DIRBE). There are ten horn antennas, all of which have an approximately Gaussian main beam with a 7 degrees FWHM. The pair of horns for each channel are pointed 60 degrees apart, 30 degrees to each side of the spacecraft spin axis and are designated as Horn 1 and Horn 2. The differential temperature is always in the sense Horn 1 minus Horn 2. For each channel, the switching between Horns 1 and 2 is at a rate of 100 Hz, and the switched signals undergo amplification, detection, and synchronous demodulation with a 0.5 s integration period. The 53 and 90 GHz channels use two separate linearly polarized horn pairs, while the 31 GHz channels receive opposite circular polarizations in a single pair of horns. The E-planes of linear polarization for all 53 and 90 GHz channels are directed radially outward from the spacecraft spin axis. A shield surrounds the aperture plane and shields all three instruments from solar and terrestrial emission. As the spacecraft spins, a point 30 degrees from the spin axis is swept successively by the 31 GHz Horn 1, 31 GHz Horn 2, 53 GHz A and B Horns 1, 53 GHz A and B Horns 2, 90 GHz A and B Horns 1, and 90 GHz A and B Horns 2 respectively. See Figure 8 of Bennett et al. (1992) for a schematic of the COBE aperture plane. Pixelized Differential DMR Data The corrected, baseline-subtracted and calibrated time-ordered data were sorted according to the pixel number seen by Horn 1, and then by the pixel number seen by Horn 2. All such data for a given pixel pair were then combined into four statistics: the sums of the first to fourth powers of the differential temperatures. These sums, the Horn 1 and 2 pixel numbers, and the number of occurrences of each pixel permutation comprise the DMR Pixelized Differential Data Project Data Set. Note that linear polarization information for 53 and 90 GHz is retained since the E-plane is perpendicular to the great circle joining the two pixels. For each channel, there are over 1,600,000 pixel permutations of the 6144 pixels. Section 5.3.2 describes the information given for each pixel permutation. DMR Sky Maps Within six months, each DMR channel repeatedly sampled well over a million pixel permutations (after that, the number of newly sampled pixel permutations grew much more slowly since COBE's orbital plane had by then completed its initial sweep of the sky). These pixel permutations provide a highly redundant set of data in the form of differences between pairs of the pixel temperatures. By setting these differences up as equations, we effectively collapse the redundancy by forming the chi^2 sum of the measurements involving each pixel, and forcing its derivative with respect to the pixel temperatures to be zero. There are P normal equations in the pixel temperatures, where P is the number of pixels. Because of the 60 degrees constraint of the horn separations, the P x P matrix of normal equation coefficients is only a few percent filled (hence it is a sparse matrix). By iterative techniques (see Janssen & Gulkis 1992), we solve for the sky temperature for each pixel simultaneously with coefficients of systematic error models. Since the instrument only measures temperature differences between different sky directions, these maps would be identical if the whole sky changed in temperature by a constant amount. Section 5.3.2 describes the information given for each pixel. A higher order of pixelization has been used within 20 degrees of the Galactic plane and those pixels were then averaged together in the Sky Maps Project Data Set so that the pixels are all of equal area, 6.7 square degrees. The noise level of the DMR Sky Maps Project Data Set varies by more than a factor of two over the sky owing to differences in sky coverage during the mission. The greatest redundancy is on rings of 60 degrees diameter centered at the North and South ecliptic poles since those regions are sampled on every orbit. The least redundancy is near the ecliptic plane owing to the presence of the Moon (data is not used when either DMR horn is within 21 degrees of the Moon). For channels 31A and 31B, the more stringent limits on the position of the limb of the Earth relative to the shield and the rejection of data during the two months when there is an eclipse of COBE by the Earth also reduce coverage considerably for certain pixels. Section 5.3.3 gives the maximum, mean, and minimum coverages and the corresponding pixel-to-pixel RMS noise levels. Note that since the DMR beam covers several pixels, the RMS uncertainty in the determination of the strength of a point source is about 0.6 that of the pixel-to-pixel RMS noise. Of course, the DMR was designed to be insensitive to point sources: a 1,000 Jy point source would yield peak antenna temperatures of 1.55 mK, 0.54 mK, and 0.19 mK at 31.5, 53, and 90 GHz respectively. References Bennett, C. L., et al. 1992, "COBE Differential Microwave Radiometers: Calibration Techniques," Ap.J., 391, 466-482. Janssen, M. A., & Gulkis, S. 1992, "Mapping the Sky with the COBE Differential Microwave Radiometers," in The Infrared and Submillimeter Sky after COBE, eds. M. Signore & C. Dupraz (Dordrecht: Kluwer). Smoot, G., et al. 1990, "COBE Differential Microwave Radiometers: Instrument Design and Implementation," Ap.J., 360, 685-695. 5.3.2 DMR Data Records Pixelized Differential Data Project Data Sets --------------------------------------------- Field 1 Pixel number (0 to 6143) for Horn 1 Field 2 Pixel number (0 to 6143) for Horn 2 Field 3 Number of differential antenna temperatures, Delta T Field 4 Sum Delta T Field 5 Sum (Delta T)^2 Field 6 Sum (Delta T)^3 Field 7 Sum (Delta T)^4 Noise level (per meas) 31A: 58.7 mK 31B: 60.5 mK 53A: 23.2 mK 53B: 27.1 mK 90A: 40.0 mK 90B: 30.3 mK Sky Maps Project Data Set ------------------------- Pixel number (0 to 6143) Antenna temperature, dipole subtracted (mK) Number of observations Estimated pixel uncertainty (mK) Ecliptic longitude Ecliptic latitude Galactic longitude Galactic latitude Right ascension Declination 5.3.3 DMR Data Quality Summary DMR Channel 31A 31B 53A 53B 90A 90B Max obs per pixel 71145 62839 81271 81400 81490 81669 Noise level (mK) 0.206 0.233 0.079 0.087 0.141 0.099 Mean obs per pixel 29728 24484 35672 35681 35655 35643 Noise level (mK) 0.319 0.372 0.119 0.132 0.214 0.150 Min obs per pixel 11506 7988 21526 21471 21579 21557 Noise level (mK) 0.513 0.653 0.153 0.170 0.274 0.193 5.4 FIRAS PROJECT DATA SETS 5.4.1 FIRAS Product Description The June 1994 data products consist of both calibrated sky maps and uncalibrated, time-ordered data. The former are of most interest to investigators. There are three types of calibrated maps: the calibrated complex spectra themselves, line emission maps, and continuum emission maps. For each type of map there are ten files, eight of which correspond to combinations of detector and instrument scanning state, and two of which are averaged master maps, one at low resolution covering the entire frequency range, and one at high resolution covering the range 1 - 20 cm^(-1). There are two high frequency and two low frequency FIRAS detectors, called, respectively Right High (RH), Left High (LH), Right Low (RL), and Left Low (LL). For each detector, there are four mirror scan modes corresponding to two speeds x two lengths. The mirror scan modes are thus called Long Slow (LS), Short Fast (SF), etc. The eight detector/scan mode combinations for which we have useful data are: RHSS LHSS RHSF LHSF LLSS LLLF RLSS RLLF where the first two letters designate the detector and the last two the mirror scan mode. All eight maps and their corresponding covariance matrices have also been combined into a grand average low spectral resolution map and matrix. (This is the ninth of the ten delivered maps.) The last map is a combination of the low frequency detector data taken with long mirror scans, i.e. LLLF and RLLF. This last map is a high spectral resolution map spanning the low frequency range only. These two average maps, and the associated line emission and dust continuum maps derived from them, are the products likely to be of most astrophysical interest. The FIRAS data also consist of uncalibrated average interferograms for each pixel, averaged calibration interferograms, and the calibration models themselves. There is one such model for each of the eight detector/instrument state combinations. Finally, there is Level 1 instrument data. This consists of raw interferograms and engineering data, pixel- and time-ordered indices of these data, instrument state information, and assorted reference data sets. More detail is given about each data set below. 5.4.2 FIRAS Data Record The following table lists all of the data products. Data Set and Distribution Number of Total Size Time-order Medium (1) files (2) (MB) or sky map Format(3) ------------------------- --------- ---------- ---------- --------- Calibrated data --------------- Sky spectra F,C,T 10 400 map FITS Line emission maps F,C,T 10 40 map FITS Line profiles F,C,T 2 1 N/A (4) FITS Dust maps F,C,T 10 40 map FITS Covariance matrices F,C,T 10 25 map (5) FITS Uncalibrated data ----------------- Averaged sky interferograms C,T 176 600 map native Averaged cal interferograms C,T 40 80 time native Calibration models F,C,T 8 20 time FITS Raw data and indices -------------------- Raw interferograms T 1224 3500 time native Engineering data T 306 600 time native Sky interferogram index T 88 85 map native Calibration interferogram index T 1266 9 time native Housekeeping T 328 250 time native Mirror scan data T 328 170 time native Reference data sets T 20 50 time native Notes: (1) Distribution media are F for anonymous FTP, C for CD-ROM, and T for tape. For calibrated sky maps, only the two channel and scan mode-averaged "master maps" will be available by FTP; the eight channel and scan mode maps are available via tape and CD-ROM. (2) Number of files should not be confused with number of records in each file. For calibrated sky maps, there is one record per pixel in each file; for raw interferograms there is one file for each day of the mission, times the number of detectors (four). (3) ITS files are in the binary table extension and are readable with the FITSIO package available via anonymous FTP from legacy.gsfc.nasa.gov. The files are written with one record per pixel, in pixel numerical order. Native format files are also written in pixel order but are not FITS: they are VAX binary files and require byte-swapping for IEEE conformance. Each file in native format is accompanied by a so-called Record Definition Language (RDL) file detailing the file record structure. The RDL is an ASCII file that gives data field names and byte offsets within each record. (4) List of line profiles associated with each spectral line. One file applies to high resolution spectra, the other to low. (5) Covariance matrices are not maps themselves, but each is associated with a map. Each matrix is a 167 x 167 matrix giving frequency-to- frequency variances of the calibrated spectra within each map. Primary Data Sets ----------------- The following data sets are of primary interest to investigators: Sky spectra are the ten sky maps consisting of complex calibrated spectra spanning the FIRAS frequency range. Each map contains all sky pixels. The record for each pixel includes the average spectrum, formal variances at each frequency point, the number of observations; the centroid of the data in Galactic, ecliptic, and equatorial coordinates; and the average value of engineering quantities (e.g., bolometer temperatures) associated with the spectrum. Line emission maps correspond to the sky maps, but have 16 data points in each pixel, consisting of the integrated line intensities (in units of W/m^2/sr) in the following lines: Spectral Lines in FIRAS Data ---------------------------- Species nu (cm^(-1)) nu (GHz) lambda (um) ------- ------------ -------- ----------- CO (J=1-0) 3.84 115.27 2601. CO (J=2-1) * 7.69 230.54 1300. CO (J=3-2) * 11.53 345.80 867.0 O2 14.17 424.75 705.8 CO (J=4-3) * 15.38 461.04 650.3 [C I] * 16.41 492.22 609.1 H2O 18.58 556.89 538.3 CO (J=5-4) * 19.22 576.27 520.2 CO (J=6-5) 23.07 691.47 433.6 [C I] * 27.00 809.44 370.4 H2O 37.13 1113.3 269.3 [N II] * 48.74 1461.1 205.2 [C II] * 63.40 1900.5 157.7 [O I] 68.71 2060.1 145.5 [Si I] 77.11 2311.7 129.7 [N II] * 82.04 2459.4 121.9 (Asterisks indicate detections that were published in Wright et al., 1991.) Line maps corresponding to the high resolution scan modes contain data only for lines at frequencies below 20 cm^(-1). In all maps a continuum has been subtracted from each line. The data set consists of the line intensities, the formal errors in those intensities, and the coefficients of a polynomial baseline subtracted from the spectrum after first removing a dust continuum. Line profiles are in two files, each with a list of synthetic spectra. Each such spectrum contains a single spectral line convolved with the instrumental profile. There are 16 such spectra in one file corresponding to the 16 spectral lines listed above. Each spectrum is 167 points long, and corresponds in frequency scale and resolution to the low resolution calibrated maps. The other file contains profiles only for the six lines at frequencies below 20 cm^(-1), and corresponds to the 36-point high resolution spectra. Dust maps are maps of dust optical depth, temperature, and emissivity for a two-component dust model. Covariance matrices are in units of MJy^2/sr^2. There is one such matrix for each sky map, of dimension N x N, where N is the number of frequency points. (N=167 for low resolution spectra and 36 for high.) The matrices are symmetric, and the unique triangular elements are packed into the FITS file. The FIRAS Explanatory Supplement contains the algorithm and pseudocode for unpacking the data file into a square, symmetric matrix. Secondary Data Sets ------------------- The following data sets require extensive data processing to be of astrophysical use but can in principal be used to reconstruct and reprocess the primary data sets. They can also be used to establish trends in instrument performance and identify periods of anomalous instrument behavior. Each data set comes with documentation that explains the utility of each field in the record. Averaged sky interferograms are the coadded raw data in each pixel. These interferograms have undergone internal consistency checking and baseline and glitch removal but are not calibrated and have not been Fourier transformed into spectra. There may be more than one coadd per pixel. Each record consists of the data and its variance, the averaged sky position of the observations, the instrument scan mode, and the corresponding coadded engineering quantities such as detector voltages and mirror temperatures. Averaged cal interferograms are analogous to the averaged sky interferograms, but are sorted by calibrator temperature instead of sky pixel. Calibration models correspond to the eight delivered detector/mirror scan mode maps. Each model file gives the system optical efficiency; and the emissivities of the sky and reference antennas, the reference blackbody, the scanning mirrors, and the bolometers themselves. It also includes parameters for the bolometer responsivity model and coefficients for correcting for vibrational resonances in the mirror scan platform. Consult the FIRAS Explanatory Supplement, available via anonymous FTP from nssdca.gsfc.nasa.gov, for details. Raw interferograms are stored as one file per detector per mission day. Each file contains roughly 1000 raw interferogram records, each in units of digital counts. Other information for each observation includes gain and mirror scan settings, attitude information, data quality flags, and onboard microprocessor status words. Engineering data are also stored as one file per mission day, with about 1000 records per file. Engineering records consist of all instrument temperatures, voltages, and status bits, in appropriate units. Time tags of the engineering records, and the values within the records, have been interpolated to match up with raw interferogram collection times. Sky interferogram index refers to a set of abbreviated raw interferogram records, sorted by sky pixel. Each record consists of the pixel number, instrument state, and time tags of the raw interferograms that match that pixel and state. Calibration interferogram index is analogous to the sky interferogram index, but for calibration data. In this case the sorting is by calibrator temperature and instrument state, rather than pixel number and instrument state. Housekeeping data are the raw engineering data, with all quantities expressed in digital counts rather than volts, kelvins, etc. Housekeeping records are asynchronous with raw interferograms. Mirror scan data are synchronous with housekeeping data and give mirror scan speed, length, and direction at 0.25 sec intervals throughout the mission. Reference data sets are small files containing various constants pertaining to instrument operation and performance, e.g., mirror scan speeds and spectrum Nyquist frequencies. References Wright, E.L., Mather, J. C., Bennett, C. L., Cheng, E. S., Shafer, R. A., Fixsen, D. J., Eplee, R. E., Jr., Isaacman, R. B., Read, S. M., Boggess, N. W., Gulkis, S., Hauser, M. G., Janssen, M., Kelsall, T., Lubin, P. M., Meyer, S. S., Moseley, S. H., Jr., Murdock, T. L., Silverberg, R. F., Smoot, G. F., Weiss, R., and Wilkinson, D. T. 1991, "Preliminary Spectral Observations of the Galaxy with a 7 Degree Beam by the Cosmic Background Explorer (COBE)," Ap. J., 381, 200. 5.4.3 FIRAS Data Quality Summary FIRAS Calibrated Spectra Data Set --------------------------------- Sky coverage 95% Frequency Range 20 - 95 cm^(-1), 600 - 2850 GHz (channels RH and LH) 2 - 20 cm^(-1), 60 - 600 GHz (channels RL and LL) Wavelength Range 105 - 5000 um Frequency Resolution 0.8 cm^(-1), 24 GHz FWHM (low resolution spectra) 0.2 cm^(-1), 6 GHz FWHM (high resolution; low frequency channels only) Frequency Step 0.56 cm^(-1), 17 GHz, complex spectra (low resolution) 0.14 cm^(-1), 4 GHz, complex spectra (high resolution) Pixelization 2.59 degrees, ecliptic coordinates Beamwidth 7 degrees circular top hat Motional smearing 2.6 degrees perpendicular to ecliptic The next table gives approximate errors and sensitivities for the best map, which is the low-resolution map combining all channels. Note that where "per pixel" numbers are given, the number refers to an "average" pixel: errors in individual pixels may vary by a large factor due to differences in number of observations per pixel. Frequency nu is in units of cm^(-1). FIRAS Errors and Sensitivity ---------------------------- 2-18 cm^(-1) 18-24 cm^(-1) 24-95 cm^(-1) ------------ ------------- ------------------ Combined error per observation (MJy/sr) 2 ~8 0.8 exp(nu/16.6) Combined error per pixel (MJy/sr) 0.5 ~2 0.01exp(nu/15.2) Correlated error (MJy/sr) 0.02 ~0.08 0.004exp(nu/15.3) Gain error (1) <0.25% ~3% 0.6% (nu < 70)(2) Notes: (1) Gain errors are estimated from fit residuals in the calibration and from comparison of observations made with different scan modes and detectors. Agreement with DIRBE calibration is 15%. (2) Gain errors rise very steeply above 70 cm^(-1), to ~25% at 95 cm^(-1). The spectral range of the high frequency channels includes the Wien region of the cosmic microwave background radiation, emission from interstellar dust, and the major far infrared cooling lines of the interstellar gas. The lines so far detected in the maps include the rotational sequence of CO for J=2-1 up to the J=5-4 transition. Most of the CO cascade is seen in the low frequency channels. There are also two lines of [C I], two of [N II], and one of [C II]. These lines are very widespread, and the [C II] line is highly correlated with the dust emission. The [N II] lines are also correlated with the dust emission but the trend is not always linear, presumably due to the higher ionization potential of the nitrogen, chemical abundance gradients, and differences in excitation conditions. Analyses of these data on dust and lines have been published by Wright et al. (1991) and by Petuchowski and Bennett (1993). The data sets include maps of these and other lines. References Wright, E.L., Mather, J. C., Bennett, C. L., Cheng, E. S., Shafer, R. A., Fixsen, D. J., Eplee, R. E., Jr., Isaacman, R. B., Read, S. M., Boggess, N. W., Gulkis, S., Hauser, M. G., Janssen, M., Kelsall, T., Lubin, P. M., Meyer, S. S., Moseley, S. H., Jr., Murdock, T. L., Silverberg, R. F., Smoot, G. F., Weiss, R., and Wilkinson, D. T. 1991, "Preliminary Spectral Observations of the Galaxy with a 7 Degree Beam by the Cosmic Background Explorer (COBE)," Ap. J., 381, 200. Petuchowski,S. J. and Bennett, C. L. 1993, "Galactic Fine Structure Lines: Morphologies of the Warm Ionized Medium," Ap. J., in press (March 10, 1993). (LASP preprint no. 92-1.) 6 CGIS SOFTWARE OVERVIEW The CGIS Executive is designed to provide an interface to the COBE data and software so that guest investigators can begin working soon after their arrival. The software at the CGIF includes the software designed specifically for the COBE data, i.e., the UIMAGE and UIDL packages, as well as some other commonly used software packages. All of these analysis tools can be accessed through the COBE Guest Investigator System (CGIS) Executive interface. For more extensive information on the CGIS software, consult the CGIS Software User's Guide. 6.1 THE CGIS EXECUTIVE The CGIS Executive is a menu-driven interface which serves, among other things, as an entrance to UIMAGE, UIDL, IRAF, and SAOimage. The interface also contains online documents such as the CGIS Software User's Guide and this Handbook. News items for all users concerning software changes are available for browsing in the Executive. Users who encounter any problems with the system or who have any comments they would like to share with us may do so easily within the Executive by simply choosing the Report Comments or Problems menu option. This will invoke the VMS editor (or an editor of your choosing). Upon completion of the edit session, your comments will be automatically mailed to the appropriate contact person. We urge all users to take advantage of this option. Be forewarned that you're not off the hook that easily -- all reports will be answered! 6.2 UIMAGE UIMAGE is a menu-driven image analysis tool written in IDL by members of the COBE project so neophyte users can manipulate data without going to the IDL command line. Skymap data is easily read in and exported through UIMAGE data input/output. The software is also equipped with many fitting routines and other analysis tools that preserve the photometric accuracy of the data regardless of the projection chosen. Chapter 4 of the CGIS Software User's Guide discusses UIMAGE functions thoroughly; in addition, each UIMAGE menu is equipped with a help option, explaining the choices available from that menu. Chapter 3 of the CGIS Software User's Guide presents a tutorial session using UIMAGE. 6.3 UIDL IDL is a commercial interactive programming language widely used on the COBE project. It provides a broad range of general data I/O, array manipulation, mathematical, and display functions. Users who are unfamiliar with IDL should browse through the manuals IDL Basics and IDL User's Guide. The smaller IDL Basics illustrates various IDL capabilities through short cookbook examples, while the User's Guide is a comprehensive guide to IDL. An IDL Reference Guide is also available for detailed information on individual routines. UIDL contains additional tools written specifically to support COBE-related analysis. The routines provide data imaging routines, fitting routines, various data input/output routines, and numerous utilities useful in COBE data analysis. Since UIDL contains all IDL routines, it is recommended that all IDL users use UIDL. Chapter 3 of the CGIS Software User's Guide is a tutorial that demonstrates useful capabilities of UIDL. The User's Guide also includes detailed information about UIDL and standard IDL help facilities, as well as listing of the UIDL routines. 6.4 ADDITIONAL ANALYSIS PACKAGES Besides UIMAGE and UIDL, several other public domain software packages are available at the CGIF. IRAF, AIPS, and SAOimage are most easily accessed through the CGIS Executive under the menu option Other Analysis Tools... (see Chapter 6 of the CGIS Software User's Guide) but can also be accessed as described below. 6.4.1 IRAF 6.4.1.1 On the VMS Workstation If you are using IRAF for the first time on this system, type IRAF at the DCL prompt to set up the system logicals. Then type MKIRAF to create a LOGIN.CL file and a [.UPARM] subdirectory. Note that you need to execute the latter command only once during your stay here. Now, to access IRAF from the DCL prompt, type CL at the DCL prompt, and your session will begin. Note that you must always use the IRAF command before typing CL. If you plan to use SAOimage as your image display tool, enter the following commands at the system prompt: $ SAOSETUP $ SPAWN/NOWAIT SAOIMAGE or spawn them from within IRAF. Remember that IRAF is case-sensitive and that input data must be in FITS format. To exit IRAF, type logout at the cl> prompt. You will have to end the SAOimage process separately by choosing etc and then QUIT from the SAOimage menu bars. 6.4.1.2 On the ULTRIX Workstation To access IRAF for the first time on the ULTRIX machine, type mkiraf at the command prompt to create a login.cl file and a uparm subdirectory. Type cl to invoke IRAF. Remember that IRAF is case-sensitive and that input data must be in FITS format. If you would like to use SAOimage as your image display tool, you will have to spawn a separate process: cl> !saoimage & Alternatively, you may spawn the SAOimage process from the command line before you enter IRAF: % saoimage & To exit IRAF, type logout at the cl> prompt. You will have to end the SAOimage process separately (choose etc, then QUIT). 6.4.1.3 Getting Help in IRAF For help while in IRAF, type help at a prompt for a one line description of the tools available at that level. (Typing a ? is equivalent to the word help in IRAF.) For example, typing help at the cl> prompt gives you the following one-liners: dataio - Data format conversion package (RFITS, etc.) dbms - Database management package (not yet implemented) images - General image processing package language - The command language itself lists - List processing package local - Local (site dependent) tasks and packages noao - The NOAO optical astronomy packages plot - Plot package softools - Software tools package system - System utilities package utilities - Miscellaneous utilities package The IRAF help command also accepts an argument, e.g., help utilities. If a package or menu name, say dataio, is the argument, IRAF lists the routines available in that package/menu with a one line description for each (similar to the list shown above). If a routine name is given as the argument, say bintxt, a text file is shown with information such as a description of the routine, its usage and parameters, cross-references, and possibly an example. A status line at the bottom of the screen indicates how to move around in the help file. These commands include: q : quit d : down one-half of a screen f or space: down one full screen j or : down one line If you scroll all the way down to the bottom of the file, IRAF automatically dumps you back to the IRAF command prompt. 6.4.2 AIPS 6.4.2.1 On the ULTRIX Workstation First log in to the aips account. (See your science support person or systems management for the account password.) Change your working directory to the FITS subdirectory, and transfer any data that you want to use in AIPS into this area, using file names in all upper case letters. Spawn an xterm window: % xterm & Switch over to the xterm window and start AIPS: % aips You will then be prompted for a printer; choose one, noting that all of these are located at the CDAC and not the CGIF. The X-AIPS TV-Screen-Server soon appears on the screen as a small icon, probably behind one of your terminal screens. Click on it to restore it to its usual size. AIPS then prompts you for your user ID number. You may choose any number greater than 1, but if you find that there is data already loaded in that area, please get out and choose another number. While AIPS displays your image, messages about trackball buttons A, B, C, and D assignments will appear in your terminal window. These have been mapped into the keypad keys , , , and , respectively. To activate the screen cursor functions, press and hold while moving the mouse. To end your AIPS session: > exit 6.4.2.2 Getting Help in AIPS There are three ways to get help in AIPS. The first way is to type HELP. This brings up a four page description of AIPS help. A second method is to type HELP taskname for a more detailed description of a function. To find out the proper usage and syntax of a function, type EXPLAIN taskname. Note: The explanation will be sent to the default printer you selected at the beginning of your session, none of which are at Goddard. If a help file is longer than one screen, press to move forward to the next screen. When you reach the bottom of a help file, AIPS automatically exits the file and brings you back to the command prompt. 6.4.3 SAOimage SAOimage works as a standalone package only on the ULTRIX workstation. Invoke it by spawning a process: % saoimage 6.5 PROGRAMMING LANGUAGE COMPILERS Programs written in FORTRAN and C can be compiled on the ULTRIX or VMS workstations. The CGIF supports the widely used International Mathematics and Statistics Library (IMSL). To link to any IMSL routines, include the object library IMSL$DIR:IMSL in your LINK statement. 6.5.1 FORTRAN 6.5.1.1 On the VMS Machines To compile and link a FORTRAN program filename.FOR on the VAX, simply type $ FORTRAN filename This creates a file filename.OBJ. Now enter $ LINK filename The result is a file named filename.EXE; to run this, type RUN filename. You do not need to enter the file name extension; the computer will automatically look for files with the default extensions given above. To find information on any command qualifiers you might want to add, type HELP FORTRAN at the prompt. 6.5.1.2 On the ULTRIX Workstation To compile and link a FORTRAN program on the ULTRIX workstation, type % f77 -o filename filename.f subroutine_1.f subroutine_2.f This produces a linked program called filename, which is executed by simply typing the filename at the % prompt. To find help information on any command qualifiers you might want to add, type man f77 at the prompt. 6.5.2 C 6.5.2.1 On the VMS Workstation The VMS workstation uses GNU C. You will need to create an options file called VAXCRTL.OPT consisting of the single line SYS$SHARE:VAXCRTL/SHARE To compile, link and run the C program PROGRAM.C, type $ GCC PROGRAM $ LINK PROGRAM, VAXCRTL.OPT/OPT, GNU_CC:[000000]GCCLIB/LIB $ RUN PROGRAM 6.5.2.2 On the ULTRIX Workstation The ULTRIX machine has two C compilers on it -- the standard DEC/ULTRIX C compiler and the GNU C compiler. We recommend the use of the latter. In the commands below, cc should be substituted for gcc to invoke the DEC C compiler. To compile, link to the math library, and run a program myprogram.c on the ULTRIX workstation, type % gcc -o myprogram myprogram.c -lm % myprogram* Further information can be obtained by typing manl gcc or (man cc) at the command line. 6.6 WORD PROCESSING PACKAGES Several word processing packages are available at the CGIF. TeX and LaTeX are supported on the ULTRIX and VMS workstations. The Macintosh supports Microsoft Word. 6.6.1 TeX and LaTeX on the VMS Workstation TeX and LaTeX files are compiled on the VAX via two commands: $ TEX filename or $ LATEX filename for TeX and LaTeX, respectively. (Be sure to include the file extension if it is not .tex.) These commands create a FILENAME.DVI file. Now use the command $ DVIPS filename.DVI for both TeX and LaTeX to create a PostScript file (filename.PS). 6.6.2 TeX and LaTeX on the ULTRIX Workstation TeX and LaTeX files are compiled on ULTRIX via two commands: $ tex filename or $ latex filename for TeX and LaTeX, respectively. (Be sure to include the filename's suffix if it is different than .tex.) These commands create a FILENAME.DVI file. Now use the command $ dvips -o PS_filename filename.dvi for both TeX and LaTeX to create a PostScript file PS_filename. 6.6.3 Microsoft Word on the Macintosh To use Microsoft Word, first double-click on the hard disk icon. Now double- click on the MICROSOFT WORD folder. Finally, double-click on Microsoft Word. This brings up a blank screen in which to begin your file. 7 OTHER PRINTED RESOURCES Guest investigators may find the following documents helpful: the Proposer Information Package, the Explanatory Supplement for each instrument, the CGIS Software User's Guide, and the COBE Software Catalog. Each of these is described in more detail in subsequent sections. All but the Explanatory Supplements may be viewed using the CGIS Executive (Documentation branch). The fastest way to get a hardcopy at your remote site is to transfer the files from the appropriate anonymous FTP host listed for each below and print them on your local printer. If you would like a hardcopy and you are visiting the CGIF or if you do not have anonymous FTP capability, contact the documentation support person listed in Table 2-1. 7.1 PROPOSER INFORMATION PACKAGE This document, intended for prospective guest investigators, provides details on the COBE data products as well as the computing hardware and software provided by the GI program. FTP host:nssdca.gsfc.nasa.gov File location:ANON_DIR:[000000.COBE.PROJECT_DATA_SETS] File names:PROPOSER_INFO_FIG1.PS(PostScript figure) PROPOSER_INFO_FIG2.PS(PostScript figure) PROPOSER_INFO_FIG3.PS(PostScript figure) PROPOSER_INFO_FIG4.PS(PostScript figure) PROPOSER_INFO_PKG.DOC(ASCII version of document; does NOT include figures) PROPOSER_INFO_PKG.PS(PostScript version of document; does NOT include figures) 7.2 EXPLANATORY SUPPLEMENTS These documents describe the released data products in great detail, as well as discussing instrument calibration and limitations of the data products. They are intended for anyone interested in an in-depth description of the data processing. FTP host: nssdca.gsfc.nasa.gov DIRBE: File location: ANON_DIR:[000000.COBE.PROJECT_DATA_SETS.DIRBE.DOC] File names: not released as of 12/13/94. Files will use .DOC extension for ASCII versions, .PS for PostScript. PostScript documents do not include any figures, so any files containing the figures must be transferred separately. DMR: File location: ANON_DIR:[000000.COBE.PROJECT_DATA_SETS.DMR.DOC] File names: DMR_PDS_EXPLANATORY_SUPPL.PS (PostScript) DMR_PDS_EXPLANATORY_SUPPL.TEX (LaTeX) DMR_PDS_PRODUCTS.DOC (ASCII) FIRAS: File location: ANON_DIR:[000000.COBE.PROJECT_DATA_SETS.FIRAS.DOC] File names: FIRAS_PDS_PRODUCTS.DOC (ASCII) FIR_APPDX_y.TEX (LaTeX appendices; y is A, B, C, D, E, or F) FIR_APPDX_C_FIGn.PS (PostScript figures for appendix C, n is 2, 4, 5, 6, 7, 8, or 9) FIR_APPDX_D_FIGn.PS (PostScript figures for appendix D; n is 1, 2A, 2B, 3, 4, 5, 6, or 7) FIR_APPDX_y.TXT (ASCII; y is G, H, or I) FIR_EXP_SUP.PS (PostScript) FIR_EXP_SUP.TEX (LaTeX) FIR_EXP_SUP_FIG5-n.PS (PostScript; n is 1, 2, or 3) FIR_MACRO.TEX (LaTeX macro file) 7.3 COBE GUEST INVESTIGATOR HANDBOOK This document. FTP host: cuba.gsfc.nasa.gov File location: pub/cobe-gi/doc File names: gihb21.asc (ASCII version; no figures) gihb21.ps (PostScript version; no figures) gihb21.wp (WordPerfect 5.1 version; no figures) gihbfigan.ps (PostScript figures for appendix A; n is 1, 2, or 3) gihbfigcn.ps (PostScript figures for appendix C; n is 1, 2, 3, or 4) One figure for this document is available only in the hardcopy. 7.4 CGIS SOFTWARE USER'S GUIDE You may find it helpful to have a copy of the CGIS Software User's Guide while using the COBE software. The guide will take you through the branches of the CGIS Executive, show you the many functions of UIMAGE, and walk you through examples in UIDL to acquaint you with its capabilities. It is also useful as a reference for UIMAGE and UIDL. FTP host: cuba.gsfc.nasa.gov File location: pub/cobe-gi/doc File names: user22yy.asc (ASCII version of the document; no figures. This document has been broken up into several files. yy is either a two-digit chapter/section number or a two-letter designation for title pages, index, etc.) user22yy.ps (PostScript version; no figures; yy as above) user22yy.wp (WordPerfect 5.1 version; no figures; yy as above) user22dn.ps (PostScript figures for appendix D; n is 1, 2AB, 2C, 3, 4, or 5.) user22gn.ps (PostScript figures for appendix G; n is 1, 2, 3, or 4.) 7.5 COBE SOFTWARE CATALOG The COBE Software Catalog is a handy reference for anyone doing data analysis using the COBE UIDL tools. The catalog lists the help files for all of the UIDL routines, as well as listing and describing unconfigured routines used by the instrument teams. Note that these unconfigured routines are not available to the guest investigator community. FTP host: cuba.gsfc.nasa.gov File location: pub/cobe-gi/doc File names: csc.asc (ASCII version) csc.ps (PostScript version) csc.wp (WordPerfect 5.1 version) 7.6 LIBRARIES AVAILABLE TO GUEST INVESTIGATORS COBE preprints are available from Susan Adams at the CGIF. Preprints from other institutions are also available for browsing but not borrowing. In addition, guest investigators have access to the Goddard library, also located in Goddard Building 21. The GSFC library is open 8 AM to 6 PM, Monday through Friday. APPENDIX A VISITING THE CGIF AIRPORTS Directions from local airports to the CGIF (see Figure A-1 for a map). From Dulles Airport: Follow signs for the Dulles Toll Road toward Washington until you reach I-495, the Capitol Beltway. Take I-495 North toward Baltimore. I-495 changes to I-95; take I-95 South. Do NOT take I-95 North to Baltimore. Get off at Exit 23, which is Route 193 (Greenbelt Road). Turn left (193 East) at the stop light. The Goddard Space Flight Center is on the left approximately 3 miles down Greenbelt Road, opposite the Cipriano Square Shopping center. From Baltimore Washington International (BWI) Airport: Follow the airport exit signs to I-295 South toward Washington. (I-295 is also known as the Baltimore Washington (BW) Parkway.) After about 18 miles, take the Greenbelt exit (Route 193). Turn left at the stop sign onto Southway. Turn left at the traffic light onto Route 193 (Greenbelt Road), heading east. The Goddard Space Flight Center is on the left 2 miles down Greenbelt Road, opposite the Cipriano Square shopping center. There is also a limousine service from BWI based two miles from GSFC that runs approximately every hour for $10. Special dropoff is available for a higher rate. (See Ground Transportation below.) From National Airport: By car (the longer but easier way): Follow the exit signs for the George Washington Memorial Parkway (I-66). Stay on I-66 for about 12 miles (keep right when it forks) until you reach I-495. Take I-495 North toward Baltimore. I-495 changes to I-95; take I-95 South. Do NOT take I-95 North to Baltimore. Get off at Exit 23, which is Route 193 East (Greenbelt Road). Turn left (193 East) at the stop light. The Goddard Space Flight Center is on the left, about 3 miles down Greenbelt Road, opposite the Cipriano Square shopping center. By car (the shorter but harder way): Follow the airport exit signs for the George Washington Memorial Parkway (I-395). Take I-395 North until it ends. Note that I-395 becomes Pennsylvania Avenue. After you cross the Anacostia Freeway and the Anacostia River on the 14th Street bridge, there is an unmarked left turn to the Anacostia Freeway heading north. Take that left and you will be on what will become the Baltimore Washington Parkway. Follow it north past the exits for the Beltway (I95). Take the next exit for Greenbelt Road (Route 193, also marked for NASA Goddard). Turn left at the traffic light. The Goddard Space Flight Center will be on your left, about a mile down Greenbelt Road and opposite the Cipriano Square shopping center. By Metro rail (minimum operating hours are 10AM to midnight): (See Figure A-2 for a map of the Metro rail lines.) Take the yellow line from National Airport toward Mount Vernon Square-UDC but get off at L'Enfant Plaza. Get on the orange line to New Carrollton. At New Carrollton, a taxi cab can be hired for about $10 to complete your trip to Goddard. Taxis line up at a staging area on the lower level of the Metro station. (See the "by car" instructions if the driver is unfamiliar with the GSFC area.) The Greenbelt station on the green line is now open, although currently the entire green line is not. Change from the yellow line to the red line at Gallery Place, then change to the green line at Fort Totten. Local bus service is available. GROUND TRANSPORTATION BWI limo: The Airport Connection II Service to BWI airport from Greenbelt with connections to Dulles and National through their downtown Washington terminal. (301) 441-2345 Metro rail: Washington's Metro rail service provides an easy way to get around the downtown Washington area. A map of the metro service area can be found on page A-6. Metro fares are usually around $1.50 per trip. Taxi services: Checker/Takoma Langley Taxi Company Dulles Airport Express Taxi Serves Prince George's County / 24 Hours Serves entire Metro Area / 24 hours (301) 270-6000 (703) 406-0003 (301) 270-2200 1 (800) 995-TAXI Diamond Cab Company Serves Prince George's County (301) 499-4800 [See file gihbfiga1.ps.] Figure A-1. Schematic of the Washington metropolitan area, showing airports and major highways. [See file gihbfiga2.ps.] Figure A-2. Schematic of the Washington Metro routes. LODGING Room release can be avoided by confirming with a credit card. If you are a government employee, specify that you qualify for the government room rate. If you do book a hotel with the government rate, the hotels may require government ID when checking in. Letters in parentheses correspond to location on Figure A- 3.) Best Western Maryland Inn Best Western - Capitol Beltway (D) 8601 Baltimore Blvd. 5910 Princess Garden Parkway College Park, MD Lanham, MD (301) 474-2800 (301) 459-1000 The Courtyard by Marriott (B) Red Roof Inn (E) 6301 Golden Triangle Drive 9050 Lanham-Severn Road Greenbelt, MD Lanham, MD (301) 441-3311 (301) 731-8830 The Courtyard by Marriott Ramada New Carrollton (F) 8330 Corporate Drive 8500 Annapolis Road Landover, MD New Carrollton, MD (301) 577-3373 (301) 459-6700 Days Inn of College Park The Holiday Inn Greenbelt (C) 9137 Baltimore Blvd. 7200 Hanover Parkway College Park, MD Greenbelt, MD (301) 345-5000 (301) 982-7000 The Greenbelt Marriott (A) 6400 Ivy Lane Greenbelt, MD (301) 441-3700 RESTAURANTS (Numbers correspond to locations on Figure A-3.) Greenway Center (2): Eastgate Shoppers World (4): Chesapeake Bagel Bakery (bagels) $3-$5 Kentucky Fried Chicken (fast food) $1-$5 Chi Chi's (Mexican) $5-$10 McDonald's (fast food) $1-$5 Jasper's (variety) $5-$15 Pizza Hut $4-$10 Wendy's (fast food) $1-$5 Safeway Market (salad/sandwiches) $3-$5 Cipriano Square (3): Beltway Plaza (1): Baskin Robbins (ice cream) $1-$3 3 Brother's Pizza $3-$8 Burger King (fast food) $1-$5 Bennigan's (variety) $5-$12 Gourmet Take-Away (deli) $3-$5 Chef's Secret (seafood) $10-$20 Hunan Village (Chinese) $5-$10 Chesapeake Bay Seafood $5-$15 Maharaja (Indian) $8-$12 Chi-Chi's (Mexican) $5-$10 Osaka (Japanese sushi) $5-$10 Hardee's (fast food) $1-$5 Popeye's Chicken (fast food) $2-$5 Wendy's (fast food) $1-$5 Some other favorites... Beijing of Greenbelt (Chinese) $5-$15 131 Centerway (Located in Old Greenbelt) (6) Sir Walter Raleigh's (steak & salad) $10-$20 6323 Greenbelt Road (Located between Greenway Center and Beltway Plaza) (5) T.G.I. Friday's (variety) $5-$15 6460 Capitol Drive (Located between Greenway Center and Beltway Plaza) (7) [See file gihbfiga3.ps.] Figure A-3. Map of hotels and restaurants near Goddard. Circled letters and numbers refer to restaurants and hotels on preceding pages. Approximate distances are: F to 4, 5 miles; 1 to Goddard, 3 miles; CDAC to Goddard, 1 mile. [Figure available in hardcopy only.] Figure A-4. Layout of the Goddard Space Flight Center. MAIN GATE- OPEN 24 HOURS * 7 DAYS A WEEK PARKWAY GATE & EAST GATE- OPEN 6 AM - 7 PM * MON-FRI ONLY 1 Space Projects Building- Cafeteria, GEWA store, I.D., Personnel, Travel, Security 2 Research Projects Lab 3 Central Flight Control & Range Operations Bldg Information Technology Center 4 Plan Operations Bldg 5 Instrument Construction & Development Lab, Health Unit 6 Space Sciences Laboratory 7 Payload Testing Facility 8 Administration Building 9 Main Gate House 10 Environmental Testing Lab 11 Applied Sciences Lab 12 Tracking & Telemetry Lab 13 Network Control Center Facility 14 Spacecraft Operations Facility 15 High Capacity Centrifuge Facility 16 Logistic & Supply Facility- Shipping and Receiving 16W Logistic & Supply Facility 17 Administrative Support Bldg- Safety office, Facilities Engineering Division 18 Administrative Support Bldg- Information Technology Center 19 Technical Support Building 20 Technical Support Building- Mailroom 21 Meteorological Systems Installation Lab, Cafeteria, Library, Credit Union 22 Space & Terrestrial Applications Facility 23 Data Interpretation Lab 24 Central Heating & Refrigeration Plant 25 NTTF and Hydromechanical Lab 26 NASA Space Science Data Center 27 Mobile Equipment Support Facility- Hazardous/waste Chemical Storage Facilities 28 Technical Processing Facility 29 Spacecraft Systems Development & Integration Facility 85 Center Management Facility 87 Gas Cylinder Storage Bldg. 88 Visitor's Center 89 Ordinance Building 90 Day Care Center 97 Plant Maintenance Support Facility 98 Center Management Facility 99 Center Management Facility +------+--+---+---+---+---+--+--+---+--+--+---+---+----+--+--+-+---+---+ | | | | | | | | | | | | | | | | | |1 A| A | +------+ | | | | | | | | | | | | | | | | |8 | | | | | | | | | | | | | | | | | | | | |1 | 1 | | +------+--+---+---+---+---+--+--+---+--+--+---+---+----+--+--+-+---+ 8 | +------+ | 3 | | | +---------+----+---+-+ +-+--+--+-+-+--+--+--+--+ +--+--+ +------+ | | |133|M+---+ | | | | | | | | | | | | | | | +--+-+-+--+ +--++-+-+-+ | | | | | | | | | | | | | +------+ | | | | |C129| |L |S| | | | | | | | | | | | | |B | | | +--+-+-+--+----+ +--+-+-+ +-+--+--+-+-+--+--+--+--+ +--+--+ | | | | | | +------+----+----+--+--+---+--+---+-+-+ | | +--+ | 114A | | | | | | |134| | | | | |1 | | | | | | | | | | | | | | |9 | +------+----+----+--+--+---+--+---+-+-+- + | |1 | Exit E +-------------+ +--+--+ x | | i | | | Offices t | | 114A M. Hauser +----+---------------+ | 158 C. Bennett | | | 134 J. Mather |L108| Homer Newell | 181 R. Shafer | | Memorial Library | 181A T. Kelsall +----+ | C129 S. Adams | | C129 CGIF | | | | Meeting Rooms | | 183 A,B |(Ground level, this area | 191 |holds the cafeteria and | |the credit union) | | | +--------------------------+ BUILDING 21 FLOOR LAYOUT APPENDIX B ACRONYMS USED IN THIS MANUAL ADB Astronomical Database ADC Astronomical Data Center ADT Absolute Date and Time (VAX time unit) AIPS Astronomical Image Processing System CDAC Cosmology Data Analysis Center CD ROM Compact Disc, Read-Only Memory CGIF COBE Guest Investigator Facility CGIS COBE Guest Investigator Support CISS COBE IDL Save Set CMB Cosmic Microwave Background COBE Cosmic Background Explorer CPU Central processing unit CSDR COBE Science Data Room DCL Digital Command Language DIRBE Diffuse Infrared Background Experiment DMR Differential Microwave Radiometer FIRAS Far Infrared Absolute Spectrophotometer FTP File Transfer Protocol GHz Gigahertz GI Guest Investigator GSFC Goddard Space Flight Center I/O Input/Output IDL Interactive Data Language IMSL International Mathematical and Statistical Libraries (replaced by just IMSL, Inc. now) IP Initial Product (first publicly released data) IRAF Image Reduction and Analysis Facility IUE International Ultraviolet Explorer NDADS NSSDC Near-Line Data Service NOAO National Optical Astronomical Observatories NODIS NSSDC's On-line Data Information Services NSSDC National Space Science Data Center PDS Project Data Sets RPM Revolutions Per Minute SPoC Single Point of Contact SWG Science Working Group UIDL Utility IDL (enhanced IDL) URL Uniform Resource Locator WWW World Wide Web APPENDIX C THE COBE SKYCUBE AND PROJECTION EQUATIONS THE COBE SKYCUBE COBE data is pixelized using a variation of a quadrilateralized spherical projection that was originally developed for Earth science databases. In this scheme, the sky is projected onto a cube (also called a skycube), with faces numbered 0 through 5. Face 0 contains the North Ecliptic Pole and face 5 contains the South Ecliptic Pole. The Ecliptic plane spans the remaining faces. (See Figures C-1 and C-2.) The reference frame for the cube is defined by axes normal to faces 1 and 0. In Geocentric Ecliptic coordinates, these directions correspond to the vernal equinox and the North Ecliptic Pole. Additional details of the quad-sphere projection, including coordinate transformations, are found in the references. The terminology used to indicate the level of resolution is resolution n, where n-1 is the number of subdivisions that were made to the face. For instance, a face with resolution 6 was subdivided 5 times, has 2^5 = 32 pixels on a side, and has 4^5 = 1024 total pixels. The standard DIRBE pixel resolution is 256 x 256 per cube face (resolution 9), with a pixel size of approximately 0.32 x 0.32 degrees. For DMR and FIRAS, the standard resolution is 32 x 32 per cube face (resolution 6), corresponding to a pixel size of about 2.6 x 2.6 degrees. Figures C-3 and C-4 illustrate the pixel numbering for both DIRBE and FIRAS/DMR resolutions. References Chan, F. K. and O'Neill, E. M. Feasibility Study of a Quadrilateralized Spherical Cube Earth Data Base, EPRF Technical Report 2-75 (CSC), March 1975. O'Neill, E. M. and Laubscher, R. E. Extended Studies of a Quadrilateralized Spherical Cube Earth Data Base, NEPRF Technical Report 3-76 (CSC), May 1976. White, R. A. and Stemwedel, S. W. 1992, "The Quadrilateralized Spherical Cube and Quad-Tree for All Sky Data," in Astronomical Data Analysis Software and Systems I, eds. D. M. Worrall, C. Biemesderfer, and J. Barnes (San Francisco: ASP), pp. 379-381. [See file gihbfigc1.ps.] Figure C-1. COBE skycube, ecliptic coordinates. [See file gihbfigc2.ps.] Figure C-2. COBE skycube, galactic coordinates. [See file gihbfigc3.ps.] Figure C-3. COBE skycube, resolution 6 pixel numbering. [See file gihbfigc4.ps.] Figure C-4. COBE skycube, resolution 9 pixel numbering. SKYCUBE PROJECTION POLYNOMIALS To create the skycube, the sky is projected onto a curvilinear grid ruled on the faces of a cube. The polynomial grid is chosen to minimize the variation in the projected area of any pixel on each face separately. The projection polynomials used by COBE can be found in Extended Studies of a Quadrilateralized Spherical Cube Earth Data Base, O'Neill E.M. and Laubscher R.E., Computer Sciences Corporation, May 1976, NEPRF Technical Report 3-76 (CSC). The polynomial coefficients used by COBE differ from those found in the reference above. The actual coefficients used by COBE are listed on the last page of this appendix. Further information about the projection polynomials can be found in the Feasibility Study of a Quadrilateralized Spherical Cube Earth Data Base, Chen F. K. and O'Neill E. M., March 1975, EPRF Technical Report 2-75 (CSC). The mapping function, also known as the direct function, is fstar(alpha,beta) = r_0 * [x_1 + x_2 + x_3] where x_1 = gammastar * alpha + (1 - gammastar) * alpha^3 x_2 = alpha * beta^2 * (1-alpha^2) * [M+(Gamma-M)*(1-alpha^2) + (1-beta^2)*Sum {C_ij*alpha^(2*i)*beta^(2*j)} i >= 0 j >= 0 x_3 = alpha^3 * (1-alpha^2) * [Omega_1 + (1-alpha^2)*Sum{D_i*alpha^(2*i)}] i >= 0 The rectangular coordinates (xi, eta) of the cube face points are related to the database coordinates (x, y) through these equations: xi = f(x,y) eta = f(y,x) where the function f (x,y), the inverse of fstar(xi, eta), is given by f(x,y) = gamma*x + (1-gamma)*x^3/r_0^2 + x*y^2*(r_0^2-x^2)*[delta+(r_0^2-y^2)*Sum{c_ij*x^(2*i)*y^(2*j)}] i >= 0 j >= 0 + x^3*(r_0^2-x^2)*[omega+(r_0^2-x^2)*Sum{d_i*x^(2*i)}] i >= 0 The other important equations that relate the many variables are: delta = [-(mu+2*gamma) + sqrt{mu^2-4*mu*gamma+4*gamma^2+16*sqrt(2)*gamma^2}] / (4*r_0^4) omega = (3-2*gamma-mu-2*r_0^4*delta) / (2*r_0^4) Omega_1 = (3-2*gammastar-mustar_1) / 2 C_ij = cstar_ij * r_0^[2*(i+j+3)] D_i = dstar_i * r_0^[2*(i+3)] deltastar = (mustar_1-mustar) / (2*r_0^4) gammastar = 1 / gamma mustar = 1 / mu M = (mustar_1-mustar) / 2 gamma_1 = 1.0 - gammstar Gamma = gammastar_1 - gammastar deltastar_1 = [(gammastar_1-gammastar)*r_0^(-4)-deltastar] / r_0^2 mustar_1 = 1 / (mu+2*r_0^4*delta) omegastar = (3-2*gammastar-mustar-2*r_0^4*deltastar) / (2*r_0^4) The actual coefficients used in the COBE projections are: delta = 0.7904864491208 c_00 = 0.141189631152 omega = -1.225441487984 c_10 = 0.0809701286525 gamma = sqrt(pi/6) c_01 = -0.281528535557 mu = sqrt(sqrt(3)*pi/2) c_11 = 0.15384112876 r_0 = 0.577350269 c_20 = -0.178251207466 M = 0.00486949181 c_02 = 0.106959469314 Omega_1 = -0.159596235474 d_0 = 0.0759196200467 gammastar = 1.37484847732 d_1 = -0.0217762490699 Gamma = -0.13161671474 APPENDIX D NETWORK ADDRESSES DECnet node name Internet node name IP Address System DECnet numbers ---------------- ------------------ ----------------- -------------- ZWICKY zwicky.gsfc.nasa.gov 128.183.87.26 15.851 = 16211 CUBA cuba.gsfc.nasa.gov 128.183.87.27 15.852 = 16212 COBECL tahiti.gsfc.nasa.gov 192.94.237.16 6.976 = 7120 STARS stars.gsfc.nasa.gov 128.183.57.28 15.22 = 15382 NSSDCA nssdca.gsfc.nasa.gov 128.183.36.23 15.188 = 15548 INDEX Acronym list. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .App. B AIPS. . . . . . . . . . . . . . . . . . . . . . . . . . 4.1, 6.4, 6.4.2, App. B C (programming language). . . . . . . . . . . . . . . . . . . . . . . . . 6.5.2 CD ROMs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.3 CGIS Executive. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 6 CGIS Software User's Guide. . . 3.1, 4.5, Ch. 6, 6.1, 6.2, 6.3, 6.4, Ch. 7, 7.4 COBE mission. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 1 orbit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 1 overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 1 skycube. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .App. C COBE Software Catalog . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 Conventions in this guide . . . . . . . . . . . . . . . . . . . . . . . . Ch. 2 Data input/output CD ROMs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.3 file transfer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 FTP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.3 magnetic tapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.2 NSSDC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 offline data I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4 dcp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.2 DECnet. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.2 DECnet copy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.1 Dialing in. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.1 DIRBE data quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.3 data record. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.2 objective. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 1 Project Data Sets. . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2.1 DMR data quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3.3 data record. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3.2 objective. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 1 Project Data Sets. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 Documentation CGIS Software User's Guide . 3.1, 4.5, Ch. 6, 6.1, 6.2, 6.3, 6.4, Ch. 7, 7.4 COBE Software Catalog. . . . . . . . . . . . . . . . . . . . . . . . . . 7.5 Explanatory Supplements. . . . . . . . . . . . . . . . . . . . . . . . . 7.2 Proposer Information Package . . . . . . . . . . . . . . . . . . . . . . 7.1 support staff. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 2 Electronic mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Explanatory Supplements . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2 File transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 FIRAS data quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.3 data record. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4.2 objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 1 Project Data Sets. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4 Floppy disks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.1 FORTRAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5.1 FTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4.3 IDL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3 IMSL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5 IRAF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.1 LaTeX ULTRIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.2 VMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.1 Macintoshes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Mail (electronic) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Microsoft Word. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.3 Modems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.1 NSSDC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 Offline data input/output CD ROMs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.3 floppy disks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.1 magnetic tapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.2 Phone list. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 2 Printers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3 Project Data Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 5 Projection polynomials. . . . . . . . . . . . . . . . . . . . . . . . . .App. C Proposer Information Package. . . . . . . . . . . . . . . . . . . . . . . . 7.1 Remote access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 4 example. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.5 SAOimage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.4.3 Single Point of Contact . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 2 Skycube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .App. C Skycube projection polynomials. . . . . . . . . . . . . . . . . . . . . .App. C Software CGIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 6 NSSDC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 Support staff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ch. 2 Tape drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.2 Telnet. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.3 TeX ULTRIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.2 VMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.1 UIDL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.3 UIMAGE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.2 Word (Microsoft). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6.3 Word processors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.6 Workstations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1 Xhost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1