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--- polarisation_sensitivity_maps [2017/08/30 10:12] – created banerji
+++ polarisation_sensitivity_maps [2017/08/30 10:50] (current) – banerji
@@ Line 1: / Line 1: @@
 === Polarisation sensitivity ===
-Some preliminary scan parameters discussed in the "Imager" telecon on 28/08/2017 [[imager telecon|Telecon 20170828]]
+Some preliminary scan parameters discussed in the [[imagerteleconnotes20170828|"Imager" telecon 28/08/2017]].
+In particular Kris plotted some hitcount maps and polarisation angle maps for the following configuration
+  * alpha = 22
+  * beta = 73
+  * T_precession = 11.751 hours
+  * T_spin = 121 s
+The following illustrates the general scan strategy employed. This is the case for CORE and LiteBIRD too.
+{{:scan_params.pdf|}}. (Ignore the instrument design at the origin)
+I performed a scan using 36 detectors for a period of $4$ years using the same scanning strategy as Kris. The detectors are spread in 9 rows, each row having an ideal configuration (0, 90, 45, 135 degrees). Each row is separated by ~9' towards increasing beta. The map is then rescaled for 144 detectors.
+{{:pol_sens_144_4.png?200|}}
+{{:pol_sens_hist.png?200|}}
+I took as an example the Band #10 at 107.5 GHz. This has a beam of 7.91'. As a rule of thumb I took the number of samples along the scan direction as 4 per FWHM. This gives me a scan frequency of ~85Hz.
+Band #10 quotes a raw sensitivity of 46 muK/sqrt(Hz). To have a comparison with results for CORE I assumed a white noise of 40 muK/sqrt(Hz). These maps can be easily rescaled for the appropriate noise.

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