Hello, Chandra Users,
An upgrade to the Chandra CalDB (version 4.4.10) for use with CIAO 4.4
has been released today to the public. The upgrade has two new items:
1) The ACIS time-dependent gain correction (T_GAIN) for the
recently-closed Epoch 49, Feb 1 through April 30, 2012.
2) *** The ACIS Contamination model file upgrade version N0007. ***
The new ACIS T_GAIN upgrade affects users of ACIS data taken since Nov
01, 2011. The T_GAIN adjustment is at the usual tiny (2% of the total
correction) level.
The new ACIS CONTAM file is significant for those users doing spectral
fitting with ACIS or ACIS/Grating observations taken since 2009. As an
example, for a 2012 observation, the new time-dependent optical depth at
700 eV has increased by 15% over the previous CONTAM model.
The ciao-install script has been updated to detect your current CalDB
version and upgrade it to CalDB 4.4.10. See the CIAO 4.4 installation
web page at
http://cxc.harvard.edu/ciao/download/
if you are already using CIAO 4.4 (released December 15, 2011) or if you
are ready to upgrade to CIAO 4.4.
For manual installation of the upgrade, please see the instruction on
the CalDB downloads web page:
http://cxc.harvard.edu/caldb/downloads/
For further information and technical details, please consult the CIAO
Release notes web page at:
http://cxc.harvard.edu/ciao/releasenotes/ciao_4.4_release.html#HowCALDB4.4.10AffectsYourAnalysis
and the CalDB 4.4.10 Release notes at:
http://cxc.harvard.edu/caldb/downloads/Release_notes/CALDB_v4.4.10.html
Cheers,
Dale Graessle
Chandra CalDB Manager
This archive was generated by hypermail 2b29 : Thu Dec 13 2012 - 01:00:11 EST