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HWRix / Haloprofile

Text and Figures to go along with the Xue et al 2015 analysis of the Galactic halo profile
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The role of the priors in Eq. 5 #6

Open HWRix opened 9 years ago

HWRix commented 9 years ago

This is an issue in response to Eric's comments: he asked how crucial the priors p(FeH) and p(M_r) are in getting the result. I will spell out my expecations; XX to check by running a few more fits.

p(FeH) only enters into the selection function, c(M_r,FeH). I would expect therefore the analysis to be very insensitive to this prior. Check (action item XX): run the simplest case (constant flattening Einasto), but set p[FeH] to be flat between -3.5 and -1.2. I would suspect that nothing changes.

The prior on M_r is a bit trickier: given a density profile, which sets p(DM), the p(Mr) determines how likely combinations m(DM,Mr) are strongly enters the S( m(DM,Mr),.. ) selection function. Check (XX action): run the simplest case, but set p(Mr)= 10^(0*Mr), p(Mr)=10^(0.64Mr) instead of p(Mr)=10^(0.32Mr) in the Mr_min and Mr_max interval.

If we set p(Mr)= 10^(0*Mr), I would expect the effective radius to come out smaller, and vice versa.

In the meantime, I add to the text that our choice of p(Mr)=10^(0.32Mr) come fem the observed (near-universal cluster giant LF).

xuexx commented 9 years ago

OK, I see. I will do the fitting as soon as possible.