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Hubble Space Telescope
COS G140L/1280 Wavelength Calibration Warning

The new COS FUV G140L/1280 mode, while similar to the previous G140L/1230 mode, covers a slightly different wavelength range. While the data that allows us to better characterize this wavelength range is being analyzed it is likely that the zero point of the wavelength scale for both segments of G140L/1280 is off by a few angstroms. We expect to finalize this analysis in the next few weeks, users are advised to consult the COS Web page for an update on the status of this analysis. Once the analysis is completed users should re- retrieve their data through OTFR.