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Hubble Space Telescope
[12/16/2013] New subarray IR dark reference files released

New dark reference files have been released for the following WFC3/IR observing modes: RAPID/SQ512SUB, SPARS25/SQ512SUB, STEP25/SQ512SUB, RAPID/SQ256SUB, SPARS10/SQ256SUB, SPARS25/SQ256SUB, RAPID/SQ128SUB, SPARS10/SQ128SUB, and RAPID/SQ64SUB.

These new files were created from a much larger number of input ramps taken over a longer timespan than the previous darks. The larger number of input ramps significantly improves signal to noise and reduces error values. For most modes, the signal to noise in the new reference files is a factor of 1.5 - 17 higher than in the previous reference files. In addition, these new darks incorporate non-linearity correction, and fix an incorrectly set header keyword value (in SCI headers of the previous CDBS darks, bunit was incorrectly set to "counts/s", when it should have been set to "counts") in the RAPID/256,RAPID/128 and RAPID/64 modes.

The new dark reference files have been available in MAST and used in OTFR as of Dec 12 2013 21:32:31 GMT. To apply the new dark reference files to observations retrieved before this date, users can either download the appropriate dark reference file(s) (listed below) and manually reprocess their observations, or simply re-retrieve them from the Archive.

Observing ModeDark Reference File Name
RAPID/SQ512SUB xcc20397i_drk.fits
SPARS25/SQ512SUB xcc2039ci_drk.fits
STEP25/SQ512SUB xcc2039di_drk.fits
(For data taken before
2011-01-09 00:00:00 GMT)

(For data taken after
2011-01-09 00:00:00 GMT)

SPARS10/SQ256SUB xcc2039ai_drk.fits
SPARS25/SQ256SUB xcc2039bi_drk.fits
RAPID/SQ128SUB xcc20394i_drk.fits
SPARS10/SQ128SUB xcc20399i_drk.fits
RAPID/SQ64SUB xcc20398i_drk.fits