Reprocessing Details

The current data products in HotGAS were produced from Level 1 events files were reprocessed using CIAO 3.2.1, & CALDB version 3.0.1. The telescope response files (or ARFs) were made using the ciao script fullarf which uses mkgarf. Responses were made both with and without the ACIS CCD quantum efficiency (QE) correction applied (files with the string nqe in their nane have NO QE correction applied). The ARFs, and individual spectral redistribution response matrices (or RMFs) were made using the ciao tool mkgrmf for each half (- or +) order of each grating (up to 3rd order). Reprocessing followed the CIAO threads for the appropriate CIAO and CALDB versions, but with one important exception. We used a narrower extraction strip than the default because we found that the default cuts off the HEG data above 8 keV, yet some of the brighter and/or well-exposed sources still have good HEG data above 8 keV. This reason for the cutoff is that the overlap of the MEG and HEG strips depends on the extraction strip widths, and if the latter are too large, a larger intersection of the MEG and HEG strips results, cutting off the HEG data prematurely. Specifically, we used width_factor_hetg=20 in the tool tg_create_mask, instead of the default value of 35.