pypeit.spectrographs.jwst_nirspec module

Module for JWST NIRSpec specific methods.

class pypeit.spectrographs.jwst_nirspec.JWSTNIRSpecSpectrograph[source]

Bases: Spectrograph

Child to handle JWST NIRSpec specific code

property allowed_mosaics

Return the list of allowed detector mosaics.

JWST/NIRSpec only allows for mosaicing the NRS1 and NRS2 detectors.


List of tuples, where each tuple provides the 1-indexed detector numbers that can be combined into a mosaic and processed by PypeIt.

Return type:


camera = 'NIRSPEC'

Name of the spectrograph camera or arm. This is used by specdb, so use that naming convention

check_frame_type(ftype, fitstbl, exprng=None)[source]

Check for frames of the provided type.


Boolean array with the flags selecting the exposures in fitstbl that are ftype type frames.

Return type:


compound_meta(headarr, meta_key)[source]

Methods to generate metadata requiring interpretation of the header data, instead of simply reading the value of a header card.


Metadata value read from the header(s).

Return type:



Return the metadata keys that define a unique instrument configuration.

This list is used by PypeItMetaData to identify the unique configurations among the list of frames read for a given reduction.


List of keywords of data pulled from file headers and used to constuct the PypeItMetaData object.

Return type:


classmethod default_pypeit_par()[source]

Return the default parameters to use for this instrument.


Parameters required by all of PypeIt methods.

Return type:


get_detector_par(det, hdu=None)[source]

Return metadata for the selected detector.

  • det (int) – 1-indexed detector number.

  • hdu (, optional) – The open fits file with the raw image of interest. If not provided, frame-dependent parameters are set to a default.


Object with the detector metadata.

Return type:


get_rawimage(raw_file, det)[source]

Read raw images and generate a few other bits and pieces that are key for image processing.

Based on

  • raw_file (str) – File to read

  • det (int) – 1-indexed detector to read


  • detector_par (pypeit.images.detector_container.DetectorContainer) – Detector metadata parameters.

  • raw_img (numpy.ndarray) – Raw image for this detector.

  • hdu ( – Opened fits file

  • exptime (float) – Exposure time read from the file header

  • rawdatasec_img (numpy.ndarray) – Data (Science) section of the detector as provided by setting the (1-indexed) number of the amplifier used to read each detector pixel. Pixels unassociated with any amplifier are set to 0.

  • oscansec_img (numpy.ndarray) – Overscan section of the detector as provided by setting the (1-indexed) number of the amplifier used to read each detector pixel. Pixels unassociated with any amplifier are set to 0.

header_name = 'jwst_nirspec'

Name of the spectrograph camera or arm from the Header. Usually the INSTRUME card.


Define how metadata are derived from the spectrograph files.

That is, this associates the PypeIt-specific metadata keywords with the instrument-specific header cards using meta.

name = 'jwst_nirspec'

The name of the spectrograph. See Spectrographs for the currently supported spectrographs.

ndet = 2

Number of detectors for this instrument.


Define the list of keys to be output into a standard PypeIt file.


The list of keywords in the relevant PypeItMetaData instance to print to the PypeIt Reduction File.

Return type:


supported = True

Flag that PypeIt code base has been sufficiently tested with data from this spectrograph that it is officially supported by the development team.

telescope = Parameter     Value  Default  Type        Callable -------------------------------------------------- name          JWST   KECK     str         False    longitude     0.0    None     int, float  False    latitude      0.0    None     int, float  False    elevation     0.0    None     int, float  False    fratio        None   None     int, float  False    diameter      6.5    None     int, float  False    eff_aperture  None   None     int, float  False   

Instance of TelescopePar providing telescope-specific metadata.

url = ''

Reference url