askap-craco / CELEBI

The CRAFT Effortless Localisation and Enhanced Burst Inspection Pipeline
MIT License
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Incorrect declination pixel reported at low declinations #458

Closed marcinglowacki closed 1 year ago

marcinglowacki commented 1 year ago

Sources identified in the field image had a different pixel to reality (e.g. 1200 rather than 1167). This error had been always present, but only became obvious at low declinations (due to the cos(dec) correction required not being accounted for).

This was attributed to the https://casaguides.nrao.edu/index.php/Analysis_Utilities set ot modules, specifically au.fineRADec function, not respecting the sin projection used for the image.

Solved by coding a separate method for the pixel identification and updating calibrateFRB.py, calibration.nf.