Python interface to the HAWK-I and HST-based JWST calibration field catalogs. Both of these catalogs have RA, Dec positions as well as estimated magnitudes for most JWST instruments+filters.
Access HAWK-I based catalog:
from jwcf import hawki
catalog = hawki.hawki_catalog()
Access HST based catalog:
from jwcf import hst
catalog = hst.hst_catalog(decimal_year_of_observation=2022.50)
decimal_year_of_observation above provides the RA, Dec locations at the desired epoch. These locations are projected based on accurate HST proper motions derived using dual-epoch data obtained in 2006.39 and 2017.38. If decimal_year_of_observation is not provided, the output catalog will default to 2017.38 positions.
The resulting catalog above is an astropy table (class). Available columns can be accessed by catalog.colnames. To extract a specific column: e.g., catalog['ra_deg'] as a table column or catalog['ra_deg'].data as a (masked) array.
Anderson, J., Fall, M., and the Astrometry Working Group, The JWST Calibration Field: Absolute Astrometry and Proper Motions with GAIA and a Second HST Epoch, Technical Report JWST-STScI-007716, STScI
Sahlmann, J., 2019, Astrometric catalog for JWST focal plane geometric calibration, Technical Report JWST-STScI-006828 STScI
Sahlmann, J., 2017, Astrometric accuracy of the JWST calibration field astrometric catalog examined with the first Gaia data release, Technical Report JWST-STScI-005492, STScI
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