discrepancy of ns-r diagram between getdist and official plot

Use of Healpix, camb, CLASS, cosmomc, compilers, etc.
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Jack Sparrow
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discrepancy of ns-r diagram between getdist and official plo

Post by Jack Sparrow » June 06 2017

When I use the getdist to plot the ns-r diagram (base_nrun_r_plikHM_TT_lowTEB_BKP), I found that the r of solid line is almost 0.12,

While in the paper

https://arxiv.org/pdf/1502.01589.pdf

There is a similar plot, Fig.21. There, the corresponding value is around 0.1.

I am curious why there is a difference based on the same data. Can somebody explian? Thanks!!

Antony Lewis
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Re: discrepancy of ns-r diagram between getdist and official

Post by Antony Lewis » June 07 2017

Fig 21 does not marginalize over running.

Jack Sparrow
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Joined: May 12 2016
Affiliation: HK

discrepancy of ns-r diagram between getdist and official plo

Post by Jack Sparrow » June 07 2017

Thanks!! But would you mind being more specific? What do you mean running? What should I do if I want to get a similar figure as Fig.21?

Thanks!

Jason Dossett
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Affiliation: The University of Texas at Dallas
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discrepancy of ns-r diagram between getdist and official plo

Post by Jason Dossett » June 08 2017

Running refers to running of the spectral index (n_run). In the chains you used n_run was varied (and thus could be marginalized over). To produce figure 21, n_run was not varied so the constraints obtained will be slightly different.

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