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                         RELEASE NOTES FOR HEASOFT 6.6.1
                                January 5, 2008
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The HEASoft 6.6.1 release is primarily driven by the release of the
Swift (version 3.0) software, but also includes updates to other packages
to mirror the current development versions in use at the HEASARC.

As the number of changes in this release are relatively small, a patch-
installer mechanism is available for users who wish to avoid re-installing
HEASoft in its entirety.  See

  http://heasarc.gsfc.nasa.gov/lheasoft/patch.html

for more details.


IMPORTANT:

  Please note that HEASoft 6.6.x is the last major distribution of HEAsoft
  in which we intend to include xspec v11. It is becoming increasingly hard
  to keep v11 up-to-date for new compilers and we do not have the resources
  to support two different versions. If there are v11 features that you are
  using and that we have omitted in the current version (v12) please let us
  know as soon as possible via the xspec12 help desk at:

     xspec12@athena.gsfc.nasa.gov


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                                    CFITSIO
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HEASOFT 6.6.1 includes some bug-fix updates to CFITSIO version 3.12:

- Fixed bug when defining the bounding box for annular region.

- Fixed bug triggered when the first region in a component is an exclude
  region.  The region selection was being ignored in this case.

- Fixed memory bug which is triggered when reading a FITS REGION extension
  with a large (> 100) number of exclude regions.

- Use explicit LONGLONG cast to prevent overflow when computing offset
  in large files.

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                                    HEASARC
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- extractor:

  Minor tweak to writing of region extensions. Now uses the EXTNAME
  convention from XMM-Newton ie REG001##. This is still consistent with
  CIAO which depends on the presence of the HDUNAME='REGION' keyword.

  Fixed two bugs :
  1. The fall-through option for GTI files of looking in the first table
     extension for the GTI data if none of the extension name matches worked.
  2. Speed improvement when writing out spectra with region filtering.

  Temporary fix for problem with making WMAP images when an annular region
  was used and the WMAP and image coordinates are the same.  In this case
  the fbbox numbers returned from select_region_setup are incorrect so we
  ignore them and fall back on the method used when the WMAP and image
  coordinates differ.

  Fixed error when regions are in detector coordinates (with no WCS type).
  Also improved error handling when the region set-up fails.

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                                    XIMAGE
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- Fixed buffer overflow in character array.


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                                     SWIFT
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- battblocks: Bug fix for parsing of global_tstart and global_tstop parsing.

- batmasktaglc: Bug fix to correct a typo in the variable name used to
  write the EBOUNDS extension.

- uvotsource: Adds subsidiary task (uvotconvreg) that enables handling of
  detector grism images.

- uvotproduct: Corrected html help file to document 'rebin' parameter.

- barycorr: Corrected html help file to correctly reflect default value
  for 'clockfile' parameter and add reference to Swift Timing Guide.

- swiftversion: Changed s/w version number.

- xrtinstrmap: Added 'XRA_PNT' and 'XDEC_PNT' keywords in output raw
  instrument map header storing the celestial coordinates of image
  reference pixels.

- xrtlccorr: Get celestial coordinates of image reference pixels from
  'XRA_PNT' and 'XDEC_PNT' keywords of raw instrument map.

- xrtpccorr: Get celestial coordinates of image reference pixels from
  'TCRVL2,TCRVL3' keywords of input event file (if ranom<0, decnom<-90).

- xrtgrblc: 
  Changed default PSF correction method to XRTLCCORR.
  Increased background region size for PC mode.
  Increased pile-up region for very high WT count rates.
  Added code to shift PC background regions, if they would go off-chip.
  New hidden parameter 'object', defines OBJECT keyword in output files
   object='DEFAULT' uses first OBJECT keyword found.
  New hidden parameter 'usetrigtime', default = 'yes'. If ='yes', light
   curves are offset by TRIGTIME keyword or trigtime parameter; if ='no',
   light curves are offset by earliest TSTART in input files.
  New hidden parameter 'usetargid', default = 'yes' determines if TARGID
    keyword is written to output files.
  Bug Fixes:
    Binning code was not properly merging bins.
    Trap zero-rows errors in fstatistic, and Xspec.
    Trap zero counts in Ximage.