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Hubble Space Telescope
COS G130M 1055 and 1096 Wavelengths are Corrected for OSM Drift and Zero-point Offsets

Data obtained with the 1055 and 1096 cenwaves of the G130M grating have their wavelengths corrected for OSM mechanism drift and zero-point offsets, as long as SEGMENT A is in use.

Flash durations for these new settings (102 and 35 seconds, respectively) could in some cases be longer than the desired science exposures. Science exposures shorter than the flash durations specified above can only be achieved by setting FLASH=NO, in which case a wavecal exposure will automatically be inserted after the science exposure.

For these new modes, science exposures obtained with Segment = B will NOT have their wavelengths corrected for OSM drift and zero-point offsets. In these cases the FLASH will be automatically set to NO and there are no constraints on the minimum exposure time for science exposures.