ROSAT News#164: Spectral Calibration of the ROSAT HRI

[Michael Arida <arida@milkyway.gsfc.nasa.gov>]

Date: Thu, 16 Apr 1998 14:00:54 -0400
Subject: Spectral Calibration of the ROSAT HRI

The ROSAT Science Data Center at SAO and the ROSAT Guest Observer
Facility at GSFC announce the release of the: 
           'Spectral Calibration of the ROSAT HRI'

The ROSAT High Resolution Imager has a limited (2-band) spectral
response.  This spectral capability can give X-ray hardness ratios on
spatial scales of 5 arcseconds.  The spectral response of the center
of the detector was calibrated before the launch of ROSAT, but the
gain decreases with time and is also a function of position on the
detector.   Over the past couple of years we have been engaged in a project
to calibrate the spectral response of the ROSAT HRI.  We find that
it is possible to obtain scientifically useful hardness ratios for sources 
near the center of the detector.  The software and data products required 
to analyze archival HRI data can be obtained from:

http://heasarc.gsfc.nasa.gov/docs/rosat/hrispec.html
or
http://hea-www.harvard.edu/rosat/rsdc_www/hrispec.html
  
Or via anonymous FTP to:
legacy.gsfc.nasa.gov
get rosat/software/hri/hrispec.tar.gz

All questions should be addressed to Andrea Prestwich (prestwich@cfa.harvard.edu)

___________________________________________________________________________
Michael Arida, (RSTX) ROSAT/ASCA GOF                LHEA/HEASARC
ph: 301-286-2291 (voice)                       Code 664, NASA-Goddard
arida@milkyway.gsfc.nasa.gov                      Greenbelt, MD 20771