These are the webpages relative to the CIAO 3.4 release
(18 December 2006). They are no longer actively updated,
however the CXC will continue limited support of CIAO 3.4
for the near future.
CIAO 3.4 users should check
the CALDB 3 website for
compatible calibration updates.
15 Dec 2008
The newest version of the Chandra Interactive Analysis of
Observations software, is CIAO
4.1, released on 15 December 2008. Read the
release notes
for detailed information. This release requires that
CALDB 4.1.0 be installed
for the software to work correctly.
If new calibration has been applied to the event file, the
grating spectrum should be re-extracted as well. It is then
possible to build grating response files (gARF, gRMF) in order
to model and fit the data in Sherpa.
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