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Bad Points in GHRS Multigroup Flat-field Files

The flat-field files in CDBS for G140L LSA (ga41342hz.r1h) and SSA (ga41342iz.r1h) have the value INDEF as their first and last points. When these files are used by CALHRS to flat-field GHRS data, the first and last values of the calibrated spectrum turn out to be 0. This is not a serious problem, but is also not what we intended. It can be easily corrected by replacing the first and last values of the flat-field files in all groups with the value 1 and recalibrating. We will be submitting new files to CDBS to correct this problem within the next week or so. The new files are h3e1400fz.r1h and h3e1400gz.r1h.

Since the resampling procedure caused this problem, only the two multi-group, resampled files intended for use with CALHRS have this problem. The first and last points are fine in the other G140L flat-field files, which are the data that went into creating the multigroup files, but are not intended for use with CALHRS.