This set of files was derived from the calibration dated July 2002 ("0207" in the file names), and was available on the main LETGS Effective Area page from August 2002 to July 2004.
Positive and Negative 1st Order Dispersed Effective Area; nominal aimpoint; Based on in-flight mid-energy QE calibration with PKS 2155-304 and 3C 273, and previous low-energy QE calibration with Sirius B and HZ43; WITHOUT microchannel plate gaps.Note: The above effective area files include a correction for the efficiency of the LETG bow-tie spectral extraction region. If you wish to use these GARFs, and do your own spectral extraction outside of CIAO, you will need to remove (divide out) the bow-tie region extraction efficiency with the following EEARF files. Also, If you want to use GARFs created by the CIAO tool MKGARF using the default bow-tie region (these GARFs will not include the extraction efficiencies), then you will need to supply the EEARF files in Sherpa manually.
Positive & Negative dispersion (ASCII)
Positive dispersion (FITS)
Negative dispersion (FITS)
(ASCII) | Positive dispersion (FITS) | Negative dispersion (FITS) |
This 0th Order Effective Area is a low estimate, derived from the above dispersed EA; the HRC-S QE non-uniformities in the above dispersed EA are NOT corrected for. The true LETG+HRC-S 0th Order Effective Area is being tested and will be higher (better).
0th Order (ASCII) (FITS)
Positive and Negative N Order Dispersed Effective Areas for nominal aimpoint Best estimate of higher orders; in the process of being tested.
NOTE: for these files, wavelength scale is already transposed (ie. order m * wave).
NOTE: These higher order effective area files are same as above, but wavelengths are not transposed.
Before using the LETGS grating response matrices please READ THIS. The following files are the combined response matrices for orders 1 through 6, obtained by multiplying the above effective areas with the RMFs currently in the CALDB.
1st Order only Positive dispersion (FITS) Negative dispersion (FITS) 1st thru 2nd Order Positive dispersion (FITS) Negative dispersion (FITS) 1st thru 3rd Order Positive dispersion (FITS) Negative dispersion (FITS) 1st thru 4th Order Positive dispersion (FITS) Negative dispersion (FITS) 1st thru 5th Order Positive dispersion (FITS) Negative dispersion (FITS) 1st thru 6th Order Positive dispersion (FITS) Negative dispersion (FITS)
The following 2 files are the LETGS response, in channel space, for a flat spectrum with intensity 1 ph/keV, for combined orders 1-6, derived from the gRSPs above. These files are similar to, but are not gARFs.
Positive dispersion (FITS) Negative dispersion (FITS)
NOTE: If you downloaded the Dec 2001 version of response matrices between Feb 14, 2002 and Jul 25, 2002, there was an error during their creation such that the correct higher-order gARFs were not used. The gRSPs now available here for version 0112 of the gARFs are correct.
Last modified: 12/06/04
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