Sky Models

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To build the sky models the experiment bandpasses are already required. So far nominal tophat bands are being used - a complete list of the center and width is in this spreadsheet. The CMB-S4 specific band list is CMB-S4 frequency bands v1.99. What a tophat bandpass actually means is a little tricky and discussed in Bandpass Convention - What does flat mean. It seems that models 00/05/08/09 use nu^-2 in spectral radiance (SR) units, while models 01/02/03 use nu^0 in SR units. (What 06 uses is not known.)

On top of LCDM the following are added:

Sky model 00

This Gaussian dust + Gaussian Sync. Since the dust and sync levels are set to the levels found in the BICEP/Keck field it wouldn't make any sense to use this model for a large sky fraction.

Sky Model 01

This is PySM run in a1d1f1s1 mode - i.e. with the default settings for AME, dust, free-free and synchrotron.

Sky Model 02

This is PySM run in a2d4f1s3 mode - GitHub for some description of what this means.

Sky Model 03

Versus 02 this switches the dust model to a Hensley/Draine model and is dubbed a2d7f1s3. (02 to 03 also marks the switch from pysm_1.0 to pysm_2.0 so the s2, f1, s3 components in principle change. Think the change is to do with the details of how the bandpass integration is being handled.)

Sky Model 04

This model switches the dust model to a Tuhin Ghosh provided model which implements dust decorrelation. See HI-based dust polarization model for r forecasts. The AME, sync and free-free components remain the same as 03

Sky Model 05

This is a toy model of dust which is highly decorrelated. See Toy highly decorrelated dust model. There is NO AME/sync/Free-free - only dust.

Sky Model 06

This is a model from Raphael Flauger and Brandon Hensley based on MHD sims of galactic magnetic field populated with dust and relativistic electrons according to this recipe: File:Sky models.pdf.

Sky Model 08

This is the model 06 with an alternate electron energy spectrum which gives a synchrotron spectrum closer to reality.

Sky Model 09

This is the Vansyngel Model.