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sstcam / sstcam_nsb

Issue tracking and script storage for SSTCAM investigations of night sky background
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Observation Time Gain Plots #19

Open STSpencer opened 3 years ago

STSpencer commented 3 years ago

This is an issue to discuss the observation time gain plots discussed in #18. NSB has an inbuilt function to handle such things, unfortunately it works using the same system as the timespan plots, so normalisation becomes an issue again. The simplest thing I can think of to rectify this is to define some 'nominal' value of NSB and then just deal with multiples of it. The question then becomes what to take as nominal NSB. By looking at timespan plots from the 'dark field' run we did, we can figure out the corresponding value in nLb and use that:

image image

It looks to me that this is around 50 nLb (in a timespan plot) corresponding to ~30MHz (up to factors of order unity). This is what you get with the obstime function in nsb, with moonlight obs time factored in:

image

Is the Vela Pulsar the best source to be using for this? Presumably we care the most about GRBs?

STSpencer commented 3 years ago

Similar year long plot for Mrk421 I thought the galactic vs extragalactic sources comparison would be interesting to show, but it appears as if source visibility is a bigger factor:

image

STSpencer commented 3 years ago

Added fractional increase in time as additional line image image