Zero order closed loop test of performance based scaling - BK15 regen power spectra

— C. Pryke

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This posting is similar to 20190111_bkfinal_04bcd and previous. The goal is to make a zero order closed loop test of the sim pipeline. Noise numbers are taken from the published BK15 power spectra by Ben in 20190220_noiseparams_bk15_forS4. Without scaling for number of detector-years or sky area these are then fed into the CMB-S4 sim production machinery to make the 05.00 set using the actual BK15 hit map. These maps are then re-analyzed with the BK derived cross-spectra machinery to produce the power spectra below. Only the 95/150/220GHz bands are generated. The goal is to reproduce the BK band only \(\sigma(r)\) value. Ben should next re-analyze these through to ML \(r\) values alongside the standard BK15 sims - presumably using fixed \(\beta_d\), \(\beta_\mathrm{sync}\) etc. There may be a slight problem in that the standard BK sims do not contain any synchrotron but these do so it is not quite apples-to-apples.

The goal is to see if we get agreement of the \(\sigma(r)\) values. We may not exactly. The standard BK sims filter out the low \(\ell\) component and then divide out the supression resulting in increased effective \(1/f\) noise. The S4 style sims eat this extra \(1/f\) but do contain all low \(\ell\) modes - so signal sample variance will be lower. The degree to which this approximation works is presumably noise level dependent. This test is only probing the specific BK15 noise level.

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Legend for first half of the "Figure types":

Legend for second half of the "Figure types":


bp devs

Note: The contours mark the simulated bandpower in each bin closest to the respective percentile.


sum bp devs


Note: Remember that bandpower is a variance. Hence bandpower error bar is the std of a variance. This means noise and sample fluctuation components straight add, no quadrature — i.e. the difference between blue and red is the signal fluctatution component.