Closed themiyan closed 11 months ago
Looking into this further, the issue is due to the msa.fits file having objects with RA and Dec =0. When polynomial fitting is happening for a given quadrant, this results in an incorrect fit. One could do
is_src = (_shut['source_id'] > 0) & (has_offset) & (_shut['ra']>0)
here https://github.com/gbrammer/msaexp/blob/d7368560cf465a0828e942454cfcc0bbe6870278/msaexp/msa.py#L530
to fix this. No general fix requited since this is a unique case since in general msa.fits file should not have sources that satisfy this criteria (this happens in this observation because there are IDs which are >99999 which required a seperate fix in the ST NIRSpec DRP).
Hi Gabe,
For EGS,
meta_file.get_transforms
function seems to fail to reproduce accurate mapping of the slits.The polynomial coefficients for EGS Dec are quite off. i.e. expected declinations are ~ +52.8 but c0_0=67.74. Compared to values in COSMOS and UDS they all result in a significantly larger rms (see screenshot).
Thus, the
PolygonSkyRegion
computed to match positions in the sky does not resemble to correct positions in the sky.