Wilkinson Microwave Anisotropy Probe DR2

The data made available through this page has been updated. The most recent version of this data may be accessed through https://lambda.gsfc.nasa.gov/product/wmap/current/

Likelihood Software

This is the software used by the WMAP team to compute Fisher and Master matrices, and to compute the likelihoods of various models.

This software is written in Fortran 90; it has been tested with the SGI MIPSpro, NAG, and Intel Fortran 90 compilers. It requires the following libraries:

• The cfitsio library:
  http://heasarc.nasa.gov/fitsio/fitsio.html
• A set of Cholesky factorization routines. On the SGI systems, the SCSL Science Library contains the relevant routines; the LAPACK library can provide the routines on other systems.

The full tarball is 339.3MB in size, and decompresses to 594.4MB; the bulk of this space are the required data files. Please bear this in mind as you download this software. For convenience the software portion of this tarball is made available; no data is supplied, limiting its usefulness, but it is MUCH smaller.

To build it, you should edit the Makefile to support your current environment; the provided Makefile shows several possible configurations; these configurations have been tested.
Then:

make			# Builds the likelihood software library.
make check		# Builds and the test program, and diff's the output
			# to the correct results. 

Output differences of ~0.001 between platforms are normal.

Modification History:

• 2006-Mar-16 - Version 2.0 - Initial release.
• 2006-Mar-17 - Version 2.1 - Additional error reporting routines have been added to provide safe exit from the likelihood routine in the event of errors.
• 2006-Oct-16 - Version 2.2 - The main new features are:
  • The ability to evaluate the TT likelihood in pixel space up to l=30.
  • The point source correction was reduced by 18% and its uncertainty doubled.
  • The HEALPix library is no longer required to build this software.
• 2006-Oct-18 - Version 2.2.1 - Failures in the beam error module are now treated as a warning instead of an error. Warnings are not fatal to a processing run; instead the beam correction is set to zero, the problem is reported, and processing continues.
• 2006-Nov-24 - Version 2.2.2 - This version includes a faster low-l TT likelihood module, suggested by Jon Sievers of CITA. It used signal-to-noise eignemode compression to reduce the dimensionality of the covariance matrices, while retaining numerical precision. It should produce numerically equivalent results to previous releases of version 2.2. This version also fixes some memory allocation and compiler-related problems. More details concerning the speed improvement may be found in http://lambda.gsfc.nasa.gov/product/wmap/dr2/likelihood_faster_v2p2p2/

See "CHANGES" for more details describing each release.

Acknowledgements:

We thank the following individuals for useful feedback on previous versions of this code:

• Hans Kristian Eriksen
• Kevin Huffenberger
• Antony Lewis
• Hiranya Peiris
• Jon Sievers
• Licia Verde

Tarball contents

The tarball contains a data subdirectory that contains various input files. These input files are either ASCII text files containing columns of data, or FITS files containing binary data.

The tarball also contains the following files:

• README.txt
  This descriptive file.
• test.f90
  A wrapper program shows you how to call the likelihood code and allow you to run and test it. For the test data provided you should get the output stored in output.std so you may compare your output to this with a simple diff command.
• WMAP_3yr_likelihood.F90
  This is the central likelihood routine from which others are called.
  • MASTER codes for TTTT (l=2-1000) and TETE (l=2-450) + a log determinant term for TETE
  • The option of using a pixel based likelihood for TT 2≤l≤12 instead of MASTER
  • The option of using a pixel based likelihood for TE, EE and BB 2≤l≤24 (this substitutes for MASTER TETE 2<l<24.
• WMAP_3yr_options.f90
  The options/parameters for use in the code are all contained the WMAP_options module; a sample is shown below.
• WMAP_3yr_teeebb_pixlike.F90
  The low l TE/EE/BB combined pixel based analysis for l=2-23
• WMAP_3yr_tt_beam_and_ptsrc_corr.f90
  Extra chisq corrections in TTTT from the beams and point source uncertainties.
• WMAP_3yr_tt_pixlike.F90
  The low l TT pixel based likelihood code for l≤12.
• WMAP_3yr_util.f90
  IO tools and error checker.
• read_archive_map.f90/read_archive_map.fh
  A subroutine that read a skymap from a binary table in a FITS file.
• read_fits.f90/read_fits.fh
  A collections of subroutines that read two and three dimension floating point and complex arrays from the primary header/data unit of a FITS file.
• Makefile
  This is a standard makefile to compile the code.
• data/
  A directory containing data necessary to the software. One file in particular is:
  • data/fiducial_test_cls.dat
    A set of Cls for omega_c=0.25,omega_b=0.05,H0=70,ns=0.96, tau=0.1, (normalisation)As = 2.2e-9 called in test.f90.
• CHANGES
  The list of changes made since the initial release.

Additional Information

• Three-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Beam Profiles, Data Processing, Radiometer Characterization and Systematic Error Limits, N. Jarosik, et.al. (2006)
• Three-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Temperature Analysis, G. Hinshaw, et.al. (2006)
• Three-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Polarization Analysis, L. Page, et.al. (2006)
• Three-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Implications for Cosmology, D. Spergel, et.al (2006).
• The First-Year WMAP Papers
• WMAP Three Year Explanatory Supplement