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Chandra Electronic Bulletin No. 61
             |                                            |
             |              CCC  XX   XX    OOO           |
Chandra      |             CC     XX XX    OO OO          | CXC
Electronic   |            CC       XXX    OO   OO         | Number 61
Bulletin     |             CC     XX XX    OO OO          | May
             |              CCC  XX   XX    OOO           | 2007
             |                                            |

Welcome to the Chandra X-ray Center's Electronic News Bulletin Number 61.

CXC Web site: cxc.harvard.edu

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to let us know.  

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1.  Chandra Extremely Large Projects

2.  CIAO 4.0 Beta 1 and CALDB 3.4.0 Released - 16 May 2007  

3.  Chandra at the AAS 


Item 1.  Chandra Extremely Large Projects

In November 2006, the Chandra X-ray Center announced that we were considering 
the implementation of a new category for Chandra proposals and observations - 
Extremely Large Projects (ELP). The announcement described parameters of a 
possible ELP program, under which one such program ranging from 3 to 5Ms 
exposure time could be selected once every 3 years if the ELP program were 
established. The announcement called for brief white papers from interested 
individuals and teams to assess the potential scientific merit of a Chandra ELP
program, with a February 1, 2007 deadline. In response to this call, we 
received 10 White Papers.

To assess the White Papers we established 3 criteria: 
1. Demonstrated need to go beyond the current Very Large Project
   bound of 3 Ms to accomplish the key science objective(s)
2. Intrinsic science merit of the suggested program
3. Technical and scientific feasibility of program.

We determined that a program described in a White Paper should
meet all 3 of these criteria in order to support the case for
establishing Chandra ELPs.

We formed a small review team comprised of:
Harvey Tananbaum (SAO - Chandra X-ray Center Director)
Martin Weisskopf (MSFC - Chandra Project Scientist)
Belinda Wilkes (SAO - Chandra X-ray Center Assistant Director)
David Helfand (Columbia University - at-large representative).

We scored the White Papers on a scale of 1-3 for each of the 3 criteria
above (effectively weighting all of the criteria equally). We selected
a subset of the White Papers which scored highest using this procedure
in order to further assess the arguments in favor of having Chandra
ELPs based on what appeared to us to be the strongest projects. We also
generated a list of VLPs and lower scoring 2/3 of the selected LPs for
Chandra Cycles 6-8 in order to form 3 separate reference sets of science
opportunities adding to ~5Ms each, which would be representative of what 
would be displaced once every 3 years were we to proceed with Chandra ELPs. 

We met on April 13 to further discuss the White Papers and assess the
merits of establishing Chandra ELPs. We dropped the mix of Cycle 8 
VLPs and LPs from the comparison set since some of these observations are 
still in progress. We arrived at the consensus summarized next.

We believe that most, and in some cases all, of the proposed
science described in the White Papers can be accomplished within the 
current Chandra framework utilizing the category of VLPs for which 
individual proposals can range from 1-3Ms. We note that only 4 proposals
requesting 2Ms and none requesting more time have been submitted in the 
4 Cycles since the category of VLPs was instituted in Cycle 5. We do
not include Cycle 9 which is currently entering the review process. 
We can speculate about possible explanations for this situation, 
centering on strategies which proposers believe are most likely to succeed. 
We also note that none of the 4 proposals requesting 2Ms were selected,
but that Cycle 8 did see the approval of a 1.8Ms project.

It is our intent to implement a few specific steps to encourage
members of the community to consider submitting proposals for the full
3Ms currently available under VLPs when they believe the science
objectives require and merit this amount of observing time. This
message to Chandra users is a step along those lines, and we anticipate similar
words of encouragement in the next Chandra Call for Proposals. We will
also review the guidelines provided to the Peer Review Panels,
particularly the Big Projects Panel, to ensure that they give fair and
open consideration to proposals requesting times up to the 3Ms limit
of the VLP category. We discussed all of this in some detail
at the April 25-26 meeting of the Chandra Users Committee, and will fold 
relevant recommendations from the Users Committee into our future plans.

We appreciate the time invested by the teams submitting White Papers and 
anticipate achieving many of the science objectives they laid out in the 
coming years.


Item 2.  CIAO 4.0 Beta 1 and CALDB 3.4.0 Released - 16 May 2007 

The Chandra X-ray Center (CXC) is pleased to announce that version 
4.0 Beta 1 of CIAO ("Chandra Interactive Analysis of Observations") and
version 3.4.0 of CALDB are now available for download from:

[Note the new URL for the Beta software website.]

CALDB 3.4.0 may be used with both CIAO 3.4 and CIAO 4.0 Beta 1.


CIAO 4.0 Beta 1 is a tools-only release.  New versions of ChIPS and
Sherpa will be released in CIAO 4.0 Beta 2 (Summer 2007) and Beta 3
(Fall 2007).   CIAO 4.0 is planned for Winter 2007.

CIAO 3.4 is still available for download and supported as the stable
CIAO release.

The "About CIAO 4.0 Beta 1" page has more information:


The most notable tool change in CIAO 4.0 Beta 1 is that the ACIS 
dead area correction is turned on by default. There is a new version of
tgextract - named tgextract2 - which provides similar functionality, but 
allows large and asymmetric regions for better determination of background 
counts. Significant work has been done on the tool wavdetect, which has two 
new parameters. The sso_freeze tool has been enhanced so that it can create 
object-centered aspect solution which, among other uses, allows an 
object-centered exposure map to be generated. 

Read the complete release notes, including the section "How CIAO 4.0
Beta 1 and CALDB 3.4.0 Affect Your Analysis": 


In tandem with CIAO 4.0 Beta 1 is the release of the Chandra Calibration
Database version 3.4.0.  This release includes ACIS time-dependent
gain files, improved ACIS Blank-Sky background files, HRC-I gain maps,
a new HRC-S QE file, and the dispersion region file used by tgextract2.

CALDB 3.4.0 may be used with both CIAO 3.4 and CIAO 4.0 Beta 1.

Detailed information about CALDB 3.4.0 can be found in the Chandra
Calibration Database website at http://cxc.harvard.edu/caldb/


CIAO 4.0 Beta 1 is the first release of CIAO to be fully GPL
compliant.  OTS (off-the-shelf) software have been updated to current
versions.  A new test script ("smoke test") is included to aid users
in verifying installation of the release. 

CIAO 4.0 Beta 1 is distributed for the following platforms:

    * Solaris 8
    * Linux Redhat 8.0
    * Fedora Core 4
    * Mac OS X PowerPC 10.4
    * Mac OS X Intel 10.4 (native build, not under Rosetta)

This release will not work on older versions of Mac OS X.  
More details at http://cxc.harvard.edu/ciaobeta/download/platforms.html


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

CIAO 4.0 Beta 1 is a collaborative effort between the SAO/CXC Science Data
Systems, the SAO/CXC Data Systems, and MIT/CXC personnel.

Elizabeth Galle (for the CIAO development team)


Item  2. Chandra at the AAS 

As usual Chandra will be well represented at the AAS, 
particularly through posters and talks.

***  Stop by the Chandra Booth to pick up details of upcoming Chandra meetings:

X-ray Grating Spectroscopy Workshop

X-ray Summer School

8 Years of Science with Chandra

Chandra Calibration Workshop

***  For this meeting we will have experts on ACIS, CIAO, 
CHIPS, and ISIS at the Chandra booth who will be 
happy to talk with you.  Check the booth for times.
As an example, Dr. John Houck of MIT and the 
Chandra X-ray Center Science Data Systems team will be 
available to demonstrate the use of S-lang modules 
for interactive data analysis and modeling, and to answer user 
questions about these modules.  Demonstrations will include simple 
methods for making three color images of Chandra data using "evt2img", 
graphical filtering of data with "vwhere", model fitting and line 
identification for Chandra gratings analysis using ISIS, among others.  
Hours will be posted during the meeting at the Chandra booth.

***  Pick up  the latest newsletter.

***  And of course, great postcards.

See you there.

Nancy Evans  for the Chandra Team


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Last modified: 12/03/10

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