Foreground Simulation Requirements

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Foreground simulation requirements vary from group to group. Below each AWG describes what they require in foreground simulations in order for the data simulations made from those foreground models to be sufficient for addressing their flowdown questions.

Low-ell BB

For the r analysis, we need both large-scale Galactic foreground simulations and small-scale Galactic and extragalactic foreground simulations. The small scale sims are relevant for studying the impact of foreground on lensing reconstruction and thus delensing on r.

For the extragalactic foregrounds in temperature, the requirements would be similar to the Maps2OtherStats group. We will need mode detailed foreground sims in polarization than other groups, e.g. polarized point sources, small scale Galactic foregrounds.

Specifically, we would like

  • diffuse polarized foregrounds with realistic (but not totally pessimistic) levels of complication
  • non-Gaussianity in the foregrounds to test lensing reconstruction / delensing
  • models that contain small (fsky ~ 3%) regions of low polarized foreground amplitude, i.e. the BICEP/Keck patch with A_dust = 5 uK^2 at 353 GHz


Synopsis: The Foreground sim requirements for the power spectrum science are closely related to the Neutrino mass set for Maps2Other (delensing TE/EE introduces the same dependency on lensing reconstruction).


Foreground modeling / simulation requirements:

- Polarized galactic foreground simulations, ideally including non-Gaussian small-scale structure

- Temperature and polarization extragalactic foreground simulations: correlated tSZ, CIB, kSZ, sources, lensing

Simulation availability and need:

-Polarized non-Gaussian sims: mainly Vansyngel - more needed!

-Extragalactic “foregrounds”: Sehgal, Websky, Multidark, MDPL2,...

SZ, CIB spectra:

Foreground modeling / simulation requirements:

-Temperature extragalactic foreground simulations: correlated tSZ, CIB, kSZ, sources, lensing

Simulation availability and need:

-Extragalactic “foregrounds”: Sehgal, Websky, Multidark, MDPL2,...


See [[1]]


  • Clusters & proto-clusters: Something like the Websky extragalactic sky or enhanced Sehgal et al simulations are sufficient for cluster, proto-cluster, and SMG detection forecasting. Details, extragalactic simulations for 60 percent of the sky, including radio, CIB, lensing, and SZ signals, resolving down to ~a few 10^12 solar mass halos (a optical HOD would be great too). Having the simulated noise from the scanning strategy on top of that with the various depths from the deep and wide surveys would be ideal. Including variants of the experimental configurations would be great if we wanted to try and optimize for source science. A further iteration would be to have a simulated polarized extragalactic sky from websky or something like that.
  • Transients/GRBs: Can we inject sources into the TOD simulations? Can Toast do this? That's what we need.