UVIS Grism Sky Images

These are the sky images for the WFC3/UVIS G280 grism for both the calibrated, flat-fielded individual FLT exposures, as well as their corresponding CTE-corrected FLC frames. The observations used for generating the G280 sky are public on-orbit science exposures retrieved from MAST as of July 2023. The sky frames are created by stacking exposures with sources aggressively masked. The full procedure is described in ISR 2023-06.

These calibration frames can be used as input in the HSTaXe spectral extraction software by setting background subtraction to True using the backgr keyword and defining the path to the G280 sky frames using the backims keyword. For a tutorial on extracting spectra from G280 grism frames with HSTaXe, please see the G280 extraction cookbook.

FITS versions of the images are linked below. 

Change history:

v1.0 - 12/30/24 - Images were generated largely following the process described in ISR 2023-06. The only difference in the process consisted in weighting the co-adds by exposure time instead of a straight average. 

v0.5 - 11/21/23 - First release