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Space Telescope Imaging Spectrograph
Fix for CALHRS flux error

Recently a bug was found in CALHRS which led to corrupted flux values in calibrated spectra. This error occurred whenever the program attempted to access data in the vignetting calibration files in a non-sequential order. The error does not reliably repeat, and the calibrated fluxes can differ from one run of CALHRS to the next.

This problem is fixed in the version of CALHRS released with STSDAS 3.3. However, the version number on the HRS software was not properly incremented, so in the STSDAS 3.3 release the corrected version of CALHRS currently appears with the same version number (CALHRS 1.3.13) as the old erroneous one that was in STSDAS 3.2 and earlier. In future releases, this corrected version will be labeled CALHRS 1.3.14.