Dear Chandra Users and ISIS Users,
We are pleased to announce some changes in TGCat, the Chandra Gratings
Data Catalog and Archive, and in the ISIS reprocessing software.
- Web Interface:
We have changed the web interface to TGCat, the Chandra Grating Data
Catalog and Archive (<http://tgcat.mit.edu/>).
The new interface
* is menu based;
* supports multiple unified "plug in" back-end interfaces, such as
Virtual Observatory (VO) tables;
* has much smaller web data volume transfer;
* remembers user queries; and
* has an enhanced download package management interface.
For a while, the old interface will be available at
<http://tgcat.mit.edu/prev/>.
For further details, see the Announcement linked on the main page:
<http://tgcat.mit.edu/explanation.php>
- Reprocessing:
For users of the TGCat ISIS reprocessing scripts: there are two
enhancements in the latest software version:
* automatic application of the HRC-S time-dependent gain in PI
computation, IF CIAO 4.2 and the CALDB 4.2.0 are installed.
This reduces LETGS backgrounds by about a factor of 2. (See the
"HRC-S Imaging and Grating Data" section of the CIAO 4.2 Release
Notes at
<http://cxc.harvard.edu/ciao/releasenotes/ciao_4.2_release.html#HowCIAO4.2andCALDB4.2.0AffectYourAnalysis>).
* automatic (or manual) production of Type I PHA files (single
spectrum), which can be more convenient for Xspec users. The Type
II files (multi-order) will still be available.
For software information, see the "Help" menu on the main page.
- Reprocessing plans
In order to provide updated analysis-ready products which include
the HRC-S time-dependent gain-correction, and the latest updates to
ACIS contamination, we intend to reprocess all LETGS observations
and all ACIS observations since 2005 sometime in the next 2 months.
We will also add the split Type I PHA files to the data products.
We will announce completion on the web page and to this
distribution.
Regards,
David Huenemoerder, for the Grating Analysis Team.
(Send comments or feedback to tgcat@space.mit.edu)
This archive was generated by hypermail 2b29 : Thu Dec 13 2012 - 01:00:10 EST