||These updated NIRCam mask reference files are very similar to the previously released versions. The only update in these files is that the DO_NOT_USE flag has been added to all pixels that are flagged in any other way, with the exception of the reference pixels. In this way all flagged pixels will be ignored in the later stages of the calibration pipeline. Original bad pixel flags were calculated using CV3 data by the NIRCam IDT.
||Several updates to the NIRCam dark reference file rmap, which include
Remove SUBGRISM darks for detectors where the SUBGRISM apertures are not defined. These files will never be used because the subarrays they specify do not exist for the detectors listed in the file. The entries were removed in order to avoid any future confusion when it comes time to update reference files, as well as to simply clean up the rmap so users do not need to filter out these files when searching.
Added entry for SUB64FP1A and SUB64FP1B to that for SUB8FP1A and SUB8FP1B where the reference is set to NA. No dark subtraction will be done using these subarrays, but it would be helpful to add this entry so that the pipeline will not crash if someone tries to run it on these data.
Removed full frame darks with incorrect EXP_TYPE. A new set of NIRCam full frame darks were delivered which replaced the previous set of full frame darks where EXP_TYPE was erroneously set to NRC_DARK, making them unusable. The new darks have the correct EXP_TYPE value of NA, in addition to several other updates.
Removed the NRCA2 full frame dark which contained incorrect data. The file, jwst_nircam_dark_0229.fits, contained full frame dark signal for NRCA2. Since it was first delivered, the NIRCam team decided upon a new strategy for reporting the dark signal from ground testing, and this file essentially contains bad data. It was removed so that it would no longe be used. It was replaced by a file in a recent delivery.
Added the subarray, FULLP, to several of the newly-delivered darks. The darks for NRCA3, NRCALONG, NRCB1, and NRCBLONG needed FULLP added to their lists of acceptable subarrays, so that they are valid for FULL and FULLP data. Currently, the P_SUBARR keyword is not valid in the DarkModel used to create these reference files, and needed to be manually added.
||These NIRCam dark current reference files contain several improvements over the previous versions. EXP_TYPE was updated to be correct. The DQ_DEF extension was also updated to follow the standard DQ mnemonics as defined by the pipeline. Unsupported mnemonics were removed. The major change is that these files now support the new NOUTPUTS header keyword. The delivery contains a separate file for each value of NOUTPUTS, as will be done once in-flight data are collected. In this delivery, the files for the NOUTPUTS value of 1 are dummy files, with all values set to zero. This is because no single amplifier full frame darks were collected during ground testing. The files for the NOUTPUTS value of 4 contain pixel values that are identical to the previously delivered dark reference files. Longwave detector files contain signal values that are sigma-clipped means of the input files. The shortwave detector files contain signal values of zero for all nominal pixels. Hot pixels contain sigma clipped mean values.
||The context is being updated because of two separate deliveries of NIRCam subarray dark current and MIRI flatfield reference files. The NIRCam dark files contain zero signal in all pixels and groups. Not enough ground testing data were collected to produce high signal to noise dark ramps. These subarray darks each contain 400 groups, which is more than the previous versions of these files. This is enough to support the maximum allowed number of groups/frames for subarray observations, and is needed to support commissioning observations. The MIRI team delivered 8 new MIRI MRS flatfield reference files that should be integrated into CRDS and the JWST pipeline. These new files complete the transition to having the flatfield reference files be simply placeholders against the potential future split between PHOTOM and FLAT reference files. In the present CRDS version, flatfield values were unity only in the regions of the detector for which the slice mask was defined, in the new delivery flatfields are unity everywhere. Likewise, some DQ information was set in the present CRDS DQ extension that duplicated DQ information in the slice mask reference file and risked becoming out of sync. The new delivery sets the DQ flags to zero everywhere.