Reference File

The msaflagopen step uses a MSAOPER reference file.

MSAOPER Reference File

REFTYPE:

MSAOPER

Data model:

N/A

The MSAOPER reference file contains a list of failed MSA shutters and their failure state (stuck open, stuck closed, etc.)

Reference Selection Keywords for MSAOPER

CRDS selects appropriate MSAOPER references based on the following keywords. MSAOPER 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

Type Specific Keywords for MSAOPER

In addition to the standard reference file keywords listed above, the following keywords are required in MSAOPER reference files, because they are used as CRDS selectors (see Reference Selection Keywords for MSAOPER):

Keyword

Data Model Name

EXP_TYPE

model.meta.exposure.type

Reference File Format

The MSAOPER reference files are json format.

The fields are:

title:

Short description of the reference file

reftype:

Should be “MSAOPER”

pedigree:

Should be one of “DUMMY”, “GROUND” or “INFLIGHT”

author:

Creator of the file

instrument:

JWST Instrument; should be “NIRSPEC”

exp_type:

EXP_TYPEs this file should be used with; should be “NRS_IFU|NRS_MSASPEC”

telescope:

Should be “JWST”

useafter:

Exposure datetime after which this file is applicable

descrip:

Description of reference file

msaoper:
Q:

Quadrant; should be an integer 1-4

x:

x location of shutter (integer, 1-indexed)

y:

y location of shutter (integer, 1-indexed)

state:

state of shutter; should be “closed” or “open”

TA state:

TA state of shutter; should be “closed” or “open”

Internal state:

Internal state of shutter; should be “closed”, “normal” or “open”

Vignetted:

Is the shutter vignetted? Should be “yes” or “no”

history:

Description of the history relevant to this file; might point to documentation