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ratt-ru / meqtrees

A library for implementing radio astronomical Measurement Equations
http://meqtrees.net
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P-Jones and E-Jones corruption matrices applied in wrong order #789

Closed gijzelaerr closed 10 years ago

gijzelaerr commented 10 years ago
at 2010-12-08 21:59:50 Tony Willis reported:

P-Jones and E-Jones corruption matrices applied in wrong order

gijzelaerr commented 10 years ago

Original comment thread migrated from bugzilla

at 2010-12-08 21:59:50 Tony Willis replied:

At present, when doing a sky simulation with the example-sim.py script,it appears that you get the l,m position of a source, apply the beam corruption (E-Jones) to the coherency matrix followed by the parallactic angle corruption (P-Jones).However I think that you first have to apply parallactic angle corruption to the coherency matrix, so that the coherency matrix is rotated into the reference frame of the beam, and THEN apply the beam (E-Jones) corruption. This of course is also consistent with The Master's aips++ note 185. :-)

at 2010-12-13 13:19:04 Oleg Smirnov replied:

Should be fixed as of r8032. Cattery/OMS/feed_angle.py has been renamed into rotation.py. It can now be used in multiple parts of the ME (i.e. if you want to insert rotations in multiple places.) See updated example-sim.py for details.