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             |              CCC  XX   XX    OOO           |
Chandra      |             CC     XX XX    OO OO          | CXC
Electronic   |            CC       XXX    OO   OO         | Number 28
Bulletin     |             CC     XX XX    OO OO          | July
             |              CCC  XX   XX    OOO           | 2004
             |                                            |
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Welcome to the Chandra X-ray Center's Electronic News Bulletin Number 28.

CXC Web site: cxc.harvard.edu

If you would like to unsubscribe from this alias, simply reply to this message
to let us know.  

Please use this website to update your address or email: 
          http://cxc.harvard.edu/cdo/udb/userdat.html

Contents:

1. CIAO 3.1 Released
   
2. Chandra Brief Bibliography
 
3. Chandra Student Survey

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Item 1. CIAO 3.1 Released - 7 July 2004
        ===============================


The Chandra X-ray Center (CXC) is pleased to announce that version 3.1 of CIAO 
("Chandra Interactive Analysis of Observations") and version 2.27 of CALDB are 
now available for download from:
http://cxc.harvard.edu/ciao/download/

They are also available from the European mirror site at:
http://ledas-cxc.star.le.ac.uk/ciao/download/

                           -----------------------------------

CIAO 3.1 contains enhancements to the tool acis_process_events to handle the 
time-dependent ACIS gain correction. There are also bug fixes to the Data 
Model library, Sherpa, and several CIAO tools.

There is also a new "S-Lang in CIAO" web site:
http://cxc.harvard.edu/ciao/slang/ 
which starts to collect information and documentation about the use of the 
S-Lang scripting language as implemented in CIAO. Many improvements and 
additions to these "S-Lang in CIAO" web pages will be coming in the next few 
months.

For complete information on this release, please see the full Release Notes 
(http://cxc.harvard.edu/ciao/releasenotes/) which now contain new paragraphs 
"How this affects your data analysis" to help users evaluate the need of 
rerunning a processing tool in CIAO following changes in software or 
calibration.

                          -----------------------------------

In tandem with CIAO3.1 is the release of the Chandra Calibration Database 
CALDB 2.27 which contains essential elements for CIAO version 3.1, including 
ACIS T_GAIN time-dependent gain correction files.  Release Notes are available 
at:
http://cxc.harvard.edu/caldb/downloads/Release_notes/CALDB_v2.27.txt

The new acis_process_events require CALDB2.27 therefore it *must* be 
downloaded and installed (or upgraded from an earlier version) to run CIAO 3.1.

Information about CALDB 2.27 and CALDB in general can be found in the newly 
redesigned Chandra Calibration Database website at:
http://cxc.harvard.edu/caldb/

                           -----------------------------------

CIAO3.1 is distributed for the following platforms:
Solaris 2.8
Linux Redhat 6.2
Linux Redhat 8
Mac OS X 10.2.8

More details at http://cxc.harvard.edu/ciao/download/platforms.html

                           -----------------------------------

As always please send questions and requests for enhancements to the CXC 
HELPDESK (http://cxc.harvard.edu/helpdesk/)

CIAO3.1 is a collaborative effort between the SAO/CXC Science Data Systems, 
the SAO/CXC Data Systems, and MIT/CXC personnel.

Antonella Fruscione (for the CIAO development team)

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Item 2. Chandra Brief Bibliography
        ==========================

We have compiled a list of basic references and URLs intended 
to be a starting point for understanding Chandra instruments and data. 
It is deliberately limited to a few references for each topic and 
not intended to be comprehensive, just a good start.


Take a look:

http://cxc.harvard.edu/cdo/biblio/chandra_bib.html

       Nancy Remage Evans

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Item 3. Chandra Student Survey
        ======================


Thanks to all the Chandra Principal Investigators who have 
responded to our email about student involvement with 
Chandra data.  We have posted a summary of the results from 
2000 to 2003 (reprinted from Newsletter #11):

http://cxc.harvard.edu/cdo/surveys/educ/index.html

        Nancy Remage Evans and Tara Gokas
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