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Chandra Electronic Bulletin No. 20
             |                                            |
             |              CCC  XX   XX    OOO           |
Chandra      |             CC     XX XX    OO OO          | CXC
Electronic   |            CC       XXX    OO   OO         | Number 20
Bulletin     |             CC     XX XX    OO OO          | December
             |              CCC  XX   XX    OOO           | 2002
             |                                            |

Welcome to the Chandra X-ray Center's Electronic News Bulletin Number 20.

CXC Web site: cxc.harvard.edu

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1. Astro-Statistics Workshop

2. Call for Proposals


4. ATOMDB V1.3.0 

5. Announcing AstroAtom Website

6. ChaRT (Chandra Ray Tracer)  


Item 1. Astro-Statistics Workshop

 Dear colleagues,

 We invite you to participate in a Post-AAS astro-statistics workshop:

 "Current Challenges in Poisson Multi-Scale Deconvolution Methods"
		 January 15-16, 2003   
		Cambridge, Massachusetts


 This Post-AAS "Collaboratory" arises from Special Session 63:
 "Principled ``Model Free Deconvolution" via Multiscale Methods"

 It was sparked by an unusual confluence: our key AAS speakers,
 their collaborators, and Boston-area multiscale and "deconvolution"
 experts from several disciplines will all be in the Boston
 area following the AAS. We are taking this opportunity to have:
 * two days of in-depth talks by key speakers;
 *  commentaries by visiting experts; and
 * discussions by all.
 Participants are expected to range from students to seasoned reasearchers.

 * Present the cutting edge of Poisson "deconvolution" techniques using new
   multiscale methods; 
 * Hammer out current understandings, problems, and future challenges
   for Poisson multiscale methods across astronomy, medicine,
   engineering, and statistics;
 * Draft a list of questions, practical problems, challenges and new
   successes from the Special Session;
 * Provide a "gateway" for researchers new to these methods; and 
 * Lay groundwork for new collaborations and new lines of research. 
 * All with the goal of reporting back to the wider astronomical community.

 * The Astronomy and Statistics Working Group at Harvard University,
 * The Statistics Group at Boston University, 
 * NASA's AISR Program
 * The Chandra X-ray Center

 Alanna Connors, Eureka Scientific
 Peter Freeman, CXC/CfA
 Margarita Karovska, CXC/CfA
 Vinay Kashyap, CXC/CfA
 Eric Kolaczyk, Boston University
 Aneta Siemiginowska, CXC/CfA
 David van Dyk, Harvard University


Item 2. Chandra Cycle 5 Call for Proposals  

On behalf of the Chandra Project and NASA, the Chandra X-ray Center is pleased 
to announce the release of the Cycle 5 Call for Proposals (CfP). The CfP 
invites scientists to participate in the Chandra X-ray Observatory's science 
program through proposing for new observations, for archival research projects 
or for theory/modeling projects in support of understanding Chandra data.

The deadline for proposals is 7pm EST, 14 March 2003. 

The CfP may be found on the CXC web page at:


We would like to draw your attention to the following items which are 
different from Cycle 4. Please refer to the Call for Proposals (CfP) and/or 
the Proposer's Observatory Guide (POG) for more information.

** Call for Proposals (CfP): For Cycle 5, the solicitation
and selection of proposals has been delegated to SAO by NASA. As a
result, this opportunity is announced by means of this CfP, rather
than by a NASA Research Announcement (NRA) as in prior Cycles.

** Proposal Documentation: This has been reorganized. The Proposers'
Observatory Guide (POG) includes instrument and satellite descriptions,
while software and proposal preparation instructions have been replaced
by web-based science threads. Please see the Proposers' Web page on 
the CXC website.

** Updated ACIS Effective Area: The ACIS effective area (AE) for Cycle
5 has been updated to account for the time-dependent decrease in the
Quantum Efficiency of the ACIS chips. The AE provided is
estimated to be that appropriate for the middle of Cycle 5, about May

** ACIS Bright Source X-ray Photon Dose Limitations: The CXC
has adopted mission limits for the total photon dose per pixel in ACIS
of: 2,500,000 cts/pix (FI) and 62,500,000 cts/pix (BI). If your
observation calls for observing a bright point-like source close to
on-axis, we suggest you use the MARX simulator (with the parameter  
DetIdeal=yes and dither, typically, on) to calculate whether your
observation may reach 5% of the above mission limits in any one

** HRC Observing Modes: We have included a wider range of
possible observing modes for the HRC detectors. It is now possible to
select any combination of the detector (HRC-I/HRC-S), timing or regular
mode and blocking filter.

** The observation visualizer tool (ObsVis): ObsVis
has a few new capabilities including display of the satellite pitch angle
(i.e., angle from the sun to the pointing direction)
in addition to target visibility and satellite roll angle for a given  
sky position and the ability to display the default or selected
ACIS chips in the Field-of-View figures.

** Observational Constraints: New possibilities for
specifying observational constraints include: multiple 
(up to 4) window and roll constraints,
geometric progression of observing windows for monitoring
observations, and grouping a set of observations within a specified  
time period.

** TOO Response Time Bins: The classification of TOOs in
terms of their response time has been updated to more accurately
reflect the level of difficulty of responding to a request.  

** Very Large Observing Projects: Up to 3 Msec of observing
time will be available in Cycle 5 for projects requiring 1 Msec of  
observing time or more. Proposals of this type are encouraged and will
be evaluated as described for Large Projects. There will be no  
proprietary time associated with Very Large Projects.

** New Joint Observing Programs: In Chandra Cycle 5 we will offer two
additional joint programs, with the National Radio Astronomy
Observatory (NRAO) and the Rossi X-ray Timing Explorer (RXTE). Similar
to the joint program with NOAO, the Chandra peer review will be
able to allocate time on
NRAO telescopes and/or RXTE to sufficiently highly ranked proposals
that require data from these facilities in addition to Chandra in
order to address the scientific objectives. 

** Listing of previous Chandra programs: Each proposal 
must include a list of all previous Chandra programs in
which both the PI and the Observing Investigator (CoI
identified as the primary contact) for the Chandra observations
(if any) are/have been involved, including any papers
resulting from those programs.

** Education and Public Outreach (E/PO): Management of the
E/PO portion of the Chandra science program, including proposal
receipt and review, and management of approved programs, has been
transferred to the CXC for Cycle 5.


Item 3. WebGUIDE 

We are pleased to announce WebGUIDE (http://obsvis.harvard.edu/WebGUIDE), 
an interactive web site that allows access to the atomic data found in ATOMDB.
WebGUIDE currently has three functions.  "Identify" creates a linelist 
based on a user-selected wavelength range and minimum emissivity.  "Strong"
creates a linelist of strong lines at a user-selected temperature around a 
user-selected wavelength range and minimum emissivity.  Finally, "Describe"
(available either from the main page or from a linelist created by Identify
or Strong) lists the atomic parameters and references (actively linked to the 
ADS) for the data in ATOMDB.  


Item 4 ATOMDB V1.3.0

ATOMDB V1.3.0 has been released as of Friday Dec 13, 2002. A major
improvement will be the inclusion of K shell dielectronic recombination rates
for Fe XVIII through Fe XXIV, complementing the existing Fe XXV and Fe XXVI 
data.  These new rates were kindly provided by Dr. Verne Jacobs, based on
the results published in Jacobs et al. (1989, Phys Rev. A, 39, 2411). 
The wavelengths have been adjusted to match solar and tokamak 
observations.  V1.3.0 also corrects an error in the Li-like Ni XXVI line
emissivities above 1e8 K (Thanks to Eugene Churazov).  We have also fixed 
an error in some of the APED transition probabilities for hydrogenic ions 
(Thanks to Yair Krongold-Herrera).  Note that this last problem does not
affect line emissivity calculations for low-density collisional plasmas. 

See http://cxc.harvard.edu/atomdb for more information about downloading 
ATOMDB V1.3.0 and how to use it in fitting engines such as Sherpa, XSPEC, or


Item 5. Announcing AstroAtom Website

Announcing AstroAtom: http://cfa-www.harvard.edu/astroatom/
We have completed work on a new website, AstroAtom, whose goal is to foster
communication between astrophysicists and atomic physicists on areas of 
joint interest.  This was a joint project of the CXC and Institute for 
Theoretical Atomic and Molecular Physics, so we are particularly interested 
in issues relating to high-energy astrophysics and atomic physics.  

The rationale for the website is that astrophysicists and atomic physicists 
have realized for some time that they need each other, and both communities
have been attempting to increase communication between fields.  However,
cross-disciplinary work is difficult because we read different journals,
attend different conferences, and largely work on different problems.
The web is a natural vehicle to help to overcome some of these
problems.   For example, we imagine:

* An astrophysicist using Chandra LETG data discovers a line around 70\AA,
  which could be either from Si IX or Fe XI.  They post potential
  identifications to the website and asks if anyone knows of better
  wavelength measurements for these ions.
* A laboratory atomic physicist replies that their group has data on Si IX
  wavelengths, and that a follow-up measurement could be done quickly
  if needed. 
* A theoretical atomic physicist replies that they have recalculated
  the Fe XI wavelengths and transition rates using a more accurate
  configuration interaction wavefunction and a paper is in progress. 
* Physicist replies that lab measurement of Fe XI wavelengths was
  done in 1992, published in the Canadian Journal of Physics.
* And the entire thread is archived on AstroAtom for future reference.

The website accepts postings (which are moderated to eliminate spam and other
off-topic messages) from registered users, and also allows registered users
to comment on posted material.  Registration is free, and is only required to
post messages or comments.  All material on the site can be viewed and/or 
searched without registering.


Item 6. ChaRT (Chandra Ray Tracer)

We are pleased to announce a release of ChaRT (Chandra Ray Tracer):
ChaRT is a user friendly web interface
that allows the user to simulate High Resolution Mirror Assembly
(HRMA) Point Spread Functions (PSFs) at any off-axis angle and for any
energy or spectrum.

ChaRT runs remotely the same code used internally at the CXC for PSF
calibration, and it provides the user access to the best available mirror
model, including many of the details of the HRMA's physical construction and a
detailed model of the reflective properties of the mirror surface.

ChaRT verifies and submits user's simulation parameters and
notifies the user when their files are available for download via FTP.

The output of ChaRT is a FITS table containing a collection of rays. 
In order to create a model PSF image it is necessary
to project the rays onto the detector and take account of detector 
effects. This is achieved using the ChaRT rays as an input to MARX.
A set of ChaRT threads accessible from the ChaRT web page 
were designed to guide the user: 


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Last modified: 12/03/10

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