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johnsmorgan / mwa_pb_lookup

Generate primary beams based on interpolation of precalculated all-sky beams
GNU General Public License v3.0
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Code does not take into account parallactic angle #6

Closed johnsmorgan closed 4 years ago

johnsmorgan commented 4 years ago

The beams generated by https://github.com/MWATelescope/mwa_pb generate Jones matrices for Az/El beams. In order that observations taken at different Hour Angles can be combined together with coherent polarisation angles, it is necessary that these are rotated into a coordinate system which is constant with time (e.g. equatorial J2000).

In applying this correction and checking for consistency with the RTS, we also discovered a sign error in the Jones matrices.

johnsmorgan commented 4 years ago

fixed with b011ef6aa4b655e18af0bf9dad00c8b88816bffd

Note that all jones matrix lookup (hdf5) files need to be regenerated.