Difference between revisions of "Sky Models"

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On top of LCDM the following are added:
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=== Bandpasses ===
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To build the sky models the experiment bandpasses are already required.
 
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
 
So far nominal tophat bands are being used - a complete list of the center and width is
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What a tophat bandpass actually means is a little tricky and discussed in [[Bandpass Convention - What does flat mean]].
 
What a tophat bandpass actually means is a little tricky and discussed in [[Bandpass Convention - What does flat mean]].
 
Models 00/05/06/08/09 use nu^-2 in spectral radiance (SR) units, while models 01/02/03 use nu^0 in SR units. (What 04 uses is not known.)
 
Models 00/05/06/08/09 use nu^-2 in spectral radiance (SR) units, while models 01/02/03 use nu^0 in SR units. (What 04 uses is not known.)
 
On top of LCDM the following are added:
 
  
 
=== Sky model 00 ===
 
=== Sky model 00 ===

Revision as of 09:30, 30 March 2018

On top of LCDM the following are added:

Bandpasses

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. Models 00/05/06/08/09 use nu^-2 in spectral radiance (SR) units, while models 01/02/03 use nu^0 in SR units. (What 04 uses is not known.)

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 may change.)

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.