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Cosmic Background Imager |
Here we present supplementary numerical data for the CBI polarization
observations reported by J. L. Sievers et al. If you use these data in
a publication, please cite the appropriate papers and also give the
URL of this web page and the date of publication (given at the bottom
of this page).
The data are in the gzipped tar file CBI09.tar.gz (419 Kbyte)
The spectrum is contained in CBI09.newdat
This data file should work as-is with current versions of COSMOMC
(Lewis & Bridle, 2002)
File format:
first line - location of window functions (should be properly set).
second line - total bands in each polarization. Order is
TT,EE,BB,TB,TE,EB
next lines (BAND_SELECTION) - select which bands are to be used in
parameter fitting. We drop bands where WMAP5 is cosmic-variance
limited.
next line: (1 1.00 0.020) - only number of relevance is 0.020, which
is the CBI calibration uncertainty in power (1.0% in amplitude)
(ignorable line)
iliketype - COSMOMC/.newdat format support offset-lognormal
approximation to the likelihood (Bond, Jaffe, and Knox 2000).
iliketype=1 specifies the use of the offset-lognormal
approximation.
Next is a block for each polarization in the file. This file contains
only a TT power spectrum, and so there is only a single block here. This contains the
name of the polarization, then one line containing the spectrum for
each band power in the polarization. The fields are:
1) Band #
2) Power spectrum (l(l+1)C_l/2pi, in uK^2)
3) Gaussian error bar
4) Estimate of faint source contribution to the bin.
5) noise spectrum, used in the offset-lognormal approximation.
6) and 7) the lower/upper ell range contained in the band
Then a block containing the same-band correlations between
band-powers. Ones along the diagonal, with the off-diagonal terms the
degree of correlation between bands.
Finally, the Fisher matrix for the entire spectrum. Units are in uK^4. This
full matrix is used when calculating the likelihood of a spectrum in COSMOMC.
There is also a directory "windows" - in it are the band-power window
functions. There is one file for each band. Columns are
1) ell
2) W_ell/ell for. Columns are normalized, so
expected C_ell is sum(W_ell)C_ell over ell.
Last update: 2009-01-28
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