COLLIMATOR Reference File (NIRSpec only)

REFTYPE:

COLLIMATOR

Data model:

CollimatorModel

Reference Selection Keywords for COLLIMATOR

CRDS selects appropriate COLLIMATOR references based on the following keywords. COLLIMATOR is not applicable for instruments not in the table. All keywords used for file selection are required.

Instrument	Keywords
NIRSpec	INSTRUME, EXP_TYPE, DATE-OBS, TIME-OBS

Standard Keywords

The following table lists the keywords that are required to be present in all reference files. The first column gives the FITS keyword names. The second column gives the jwst data model name for each keyword, which is useful when using data models in creating and populating a new reference file. The third column gives the equivalent meta tag in ASDF reference file headers, which is the same as the name within the data model meta tree (second column).

FITS Keyword	Data Model Name	ASDF meta tag
AUTHOR	model.meta.author	author
DATAMODL	model.meta.model_type	model_type
DATE	model.meta.date	date
DESCRIP	model.meta.description	description
FILENAME	model.meta.filename	N/A
INSTRUME	model.meta.instrument.name	instrument: {name}
PEDIGREE	model.meta.pedigree	pedigree
REFTYPE	model.meta.reftype	reftype
TELESCOP	model.meta.telescope	telescope
USEAFTER	model.meta.useafter	useafter

NOTE: More information on standard required keywords can be found here: Standard Required Keywords

Reference File Format

The collimator reference file contains an astropy compound model made up of polynomial models, rotations, and translations. The forward direction is from the GWA to the MSA.

model:

Transform through the COLLIMATOR.