comomc with wmap 9 year data

Use of Cobaya. camb, CLASS, cosmomc, compilers, etc.
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jayanti prasad
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Joined: October 21 2010
Affiliation: Inter-University Centre for Astronomy and Astrophysics (IUCAA)
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comomc with wmap 9 year data

Post by jayanti prasad » July 25 2014

Hi,

Could you please let me know which version of COSMOMC and CAMB was used to get the results which are there is WMAP 9 year papers.

I have found that using a different version of CAMB Likelihood can change as much as by 1.

Another thing is that WMAP 9 year used pivot scale 0.002 Mpc^{-1} however some of the versions of COSMOMC still has it 0.05 Mpc^{-1}.

One more issue is that CAMB uses log[10^{9}As] as parameter but COSMOMC parameter file supplies log[10^{10}As] how this thing is taken into account ?

Regards
jayanti

Antony Lewis
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Joined: September 23 2004
Affiliation: University of Sussex
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Re: comomc with wmap 9 year data

Post by Antony Lewis » August 04 2014

You can change the pivot scale used by CosmoMC - the pivot_k .ini file parameter.

CAMB takes A_s directly (scalar_amp).

The version of CAMB should not significantly change WMAP results except for the Chi-Squared - the version is documented in the various WMAP papers I think.

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