GNILC dust model with stochastic small scales and variable specral index d11

[zonca]

Based on d10

d11 will have templates just at large scale saved at low nside, C_ell of small scales and map of modulation at low nside loaded from network. synalm + almxfl + alm2map to generate templates on the fly. Using a specific seed should reproduce d10 but on the fly. If seed is not specified, the small scales are stochastic.

[zonca]

@giuspugl @seclark @bthorne93 @brandonshensley any feedback?

[brandonshensley]

This sounds great. Though I am not sure why we need to store the high nside maps for d9 at all? Just to save on computation time for when you don't need many realizations?

[seclark]

Let's be sure to include positive TE in the small-scale C_ell

[zonca]

This sounds great. Though I am not sure why we need to store the high nside maps for d9 at all? Just to save on computation time for when you don't need many realizations?

correct, anyway the maps are only cached by the user if needed, so it is not a big issue.

[zonca]

Let's be sure to include positive TE in the small-scale C_ell

so, based on the notebook at: https://nbviewer.jupyter.org/gist/zonca/79f202f1d7decb59767e70fdcb46f5d6 We save just TEB in logpoltens formalism. Then when we transform back from logpoltens to IQU, we should get some TE. Do you think we should double-check that the TE we get is positive? I added TE comparison at the end between input and outputs:

there are 49 negative values out of 2049 in TE, probably to uncertainty at large scale, @seclark do you think it is a problem?

[zonca]

I have done a test where I reproduce the d9 model by using the same seed, the input maps,cl,alms used here are available at https://portal.nersc.gov/project/cmb/pysm-data/gnilc/:

https://gist.github.com/fa6e78df72230028ac027cf0e338aa74

The plan is that this model can be generated directly at any NSIDE.

I don't want to create too many models, so my proposal is:

• d9 with templates at 1024 and 8192, fixed T_d and spectral index
• d10 same templates, but variable T_d and spectral index
• d11 like d10, but stochastic (it reproduces d10 for specified seed)
• I suggest not to have a stochastic template with fixed spectral index, to avoid having too many models.

[cfenguiuc]

Is it possible to generate dust + syn with different realizations using the recent release?

[brandonshensley]

Is it possible to generate dust + syn with different realizations using the recent release?

Hi @cfenguiuc, it is now! See this issue.

[cfenguiuc]

That is awesome!!

Sincerely,

Prof. Chang Feng Department of Astronomy University of Science and Technology of China

On Fri, Mar 18, 2022 at 2:18 AM brandonshensley @.***> wrote:

Is it possible to generate dust + syn with different realizations using the recent release?

Hi @cfenguiuc https://github.com/cfenguiuc, it is now! See this issue https://github.com/galsci/pysm/issues/112.

— Reply to this email directly, view it on GitHub https://github.com/galsci/pysm/issues/84#issuecomment-1071180010, or unsubscribe https://github.com/notifications/unsubscribe-auth/AMA7DMXNO56TJAA5BHFPWHDVANZQ3ANCNFSM5EFW6JCA . Triage notifications on the go with GitHub Mobile for iOS https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675 or Android https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub.

You are receiving this because you were mentioned.Message ID: @.***>