Difference between revisions of "ForecastingSims"

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The version of code on github (v0.3) doesn't yet have small-scale realizations added, so the polarization in low S/N regions is still noisy and all maps are smoothed to 1 degree resolution. This means that power spectra of e.g. the B2 region are noisy and so Victor's method using power spectra won't instantly work.
 
The version of code on github (v0.3) doesn't yet have small-scale realizations added, so the polarization in low S/N regions is still noisy and all maps are smoothed to 1 degree resolution. This means that power spectra of e.g. the B2 region are noisy and so Victor's method using power spectra won't instantly work.
  
Solution: could try Victor's method on higher S/N regions as a test of how well things work. Or wait for the small-scales (~2 weeks). Pixel-based methods will work a little better on these sims.  
+
Solution: could try Victor's method on higher S/N regions as a test of how well things work. Or wait for the small-scale Gaussian sims (~2 weeks). Pixel-based methods will work a little better on these current v0.3 sims.  
  
 
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====(Other available codes - TBD)====
 
====(Other available codes - TBD)====

Revision as of 06:05, 13 May 2016

Simulations for forecasting r performance

Here is a selection of codes and sim maps:


PySM

Ben Thorne, David Alonso, Jo Dunkley

https://github.com/bthorne93/PySM

Spits out Nside=256 fits maps by running 'python main.py main_config.ini'. See the readme for any required dependencies.

Code already includes a few options for each component, and can be easily extended to add new inputs.


Suggested starting points and ini files for each (noise level to be adjusted):

  • over-simple 's1d1a1' = power-law synchrotron, single component dust, minimal spatial variation of indices, no polarised AME
  • towards more realism 's2d3a2' = spatial steepening of the synchrotron index away from plane, 1 component dust with spatially varying dust index sigma=0.3, 2% polarised AME.
  • towards more realism 's2d4a2' = spatial steepening of the synchrotron index away from plane, 2 component dust, 2% polarised AME


Current issues: The version of code on github (v0.3) doesn't yet have small-scale realizations added, so the polarization in low S/N regions is still noisy and all maps are smoothed to 1 degree resolution. This means that power spectra of e.g. the B2 region are noisy and so Victor's method using power spectra won't instantly work.

Solution: could try Victor's method on higher S/N regions as a test of how well things work. Or wait for the small-scale Gaussian sims (~2 weeks). Pixel-based methods will work a little better on these current v0.3 sims.


(Other available codes - TBD)