Friday, November 14, 2008

Weighting and high-frequency noise



Image of PSDs (with no normalization) of the raw (blue), delined and exponential and polynomial subtracted (white), the noise timestream (yellow), and the data (cyan).

The good: It looks like all of the powerline noise got into the noise timestream and almost none in the data.

The bad: weighting is based on the noise timestream so it's possible that the weights aren't quite right as a result

The weird: the data PSD. What's up with that? Apparently I'm preferentially subtracting certain scales but I don't know why, unless deconvolution is at fault.


Edit/Update: The deconvolution is definitely at fault. Here's the same scan done without deconvolution:



It should have been obvious; the cyan in the first plot is the PSD of the deconvolution straight up, and that should have no high-frequency structure...

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