Reorganization of the ROSAT PSPC Response Matrices in the CALDB

["Ian M George, Code 668, NASA/GSFC, USA (Usque ad mortem bibendum)" <GEORGE@lheavx.gsfc.nasa.gov>]

      Reorganization of the ROSAT PSPC Response Matrices in the CALDB
      ***************************************************************

At the request of the ROSAT GOF at NASA/GSFC:

1) the pre-existing PSPC response matrices (which include a convolution 
   with the on-axis XRT effective area, window transmission etc) formerly 
   in
        /caldb/data/rosat/pspc/cpf/*.rmf
   have been MOVED to their own sub-directory:
        /caldb/data/rosat/pspc/cpf/matrices/*.rsp
   and RENAMED (see below).
   The pre-existing matrices will be left in their current position
   (with their old names) for a grace period to be determined by the 	
   the ROSAT GOF at NASA/GSFC.

2) Additional PSPC detector redistribution matrices (which are probability 
   matrices ONLY, and DO NOT include any convolution with the XRT, windows 
   etc) have been ADDED to
        /caldb/data/rosat/pspc/cpf/matrices/*.rmf
   (see below).
   These datasets are required by the FTOOL task ftools/rosat/pcarf.

Please note that NONE of the matrices represent any improvement of the 
PSPC spectral calibration.

Further details on the new naming scheme etc can be found in 
        /caldb/data/rosat/pspc/cpf/matrices/README
which is appended below.

The ROSAT GOF will be announcing these changes to all ROSAT GOs, along with 
details on the use of PCARF, via a ROSAT Status Report in the near future.

Ian M George
NASA/GSFC, HEASARC

----------------------- Start included text ------------------------

                THE ROSAT PSPC RESPONSE MATRICES
                --------------------------------

This directory tree contains various response matrices (and related products)
for the ROSAT PSPCs.

256 PI channel detector redistribution matrices
-----------------------------------------------
  The following matrices are 2-dimensional arrays (energy vs channel)
  containing the probabilities that a photon of a given incident energy which
  enters the detector will give rise to an event in a given PI channel.
  As such they are VALID FOR ALL REGIONS of the detector, but also require
  an appropriately constructed "Ancillary Response File" (ARF) to enable
  spectral analysis to be performed in XSPEC.
  (ARFs can be constructed using the FTOOLS task ftools/rosat/pcarf)

pspcb_gain1_256.rmf
        - valid for PSPCB data taken BEFORE 1991 Oct 14
pspcb_gain2_256.rmf
        - valid for PSPCB data taken AFTER 1991 Oct 14
pspcc_gain1_256.rmf
        - valid for ALL PSPCC data (detector destroyed on 1991 Jan 25)

On-axis 256 PI channel response matrices (including the on-axis effective areas)
--------------------------------------------------------------------------------
  The following matrices are 2-dimensional arrays (energy vs channel)
  containing the above detector redistribution (probability) matrices
  BUT MULTIPLIED by the XRT effective area, window transmission etc
  appropriate for ON-AXIS sources.

pspcb_gain1_256.rsp
        - valid for PSPCB data taken BEFORE 1991 Oct 14
          (formerly known as pspcb_92mar11.rmf)
pspcb_gain2_256.rsp
        - valid for PSPCB data taken AFTER 1991 Oct 14
          (formerly known as pspcb_93jan12.rmf)
pspcc_gain1_256.rsp
        - valid for ALL PSPCC data (detector destroyed on 1991 Jan 25)
          (formerly known as pspcc_92mar11.rmf)

Old-style on-axis response matrices (including the on-axis effective areas)
---------------------------------------------------------------------------
A limited number of old-style (binary SF) matrices are available within the
'old' subdirectory. Further information can be obtained from the README file
in that directory, but the use of these matrices is STRONGLY DISCOURAGED in
favour of the FITS matrices listed above.

------------------------ End included text -------------------------