roman-corgi / corgidrp

Data Reduction Pipeline for the Roman Coronagraph Instrument
BSD 3-Clause "New" or "Revised" License
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Color correction of a source sed vs a reference sed #259

Open JuergenSchreiber opened 3 days ago

JuergenSchreiber commented 3 days ago

Describe your changes

A pipeline step that adds a reference wavelength (pivot wavelength, independent of source) of the used color filter and the color correction factor to the ext_hdr headers of the frames in a dataset (keyword names tbd and approved). I added a fluxcal module, that contains the needed functions to calculate the color correction, which is based on Gorden et al. 2022, Astronomical Journal. For absolute flux calibration the calibration factor has to be divided by the dimensionless color correction factor of a defined filter band. The color correction is need to account for different shapes of the SEDs within a band pass. I assume that the file of the CALSPEC standard star and the SED model of the observed star as well is given by the user in the CALSPEC format and unit. The csv files of the transmission curves of the color filters I have put in the data/filter_curves directory. We could make a cal file out of them, but I think that is not necessary since they won't be re-measured in space and do not change anymore. To test the code I have put a "small" calspec file in the test_data directory. I have put the pipeline step in l2b_to_l3.py which is tbc.

Type of change

Reference any relevant issues (don't forget the #)

237

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