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The CXC has extensive on-line resources for Chandra proposers and a suite of software tools for common proposal-related tasks. All proposal-related material can be found at http://cxc.harvard.edu/proposer/.
The main reference document for Chandra operation and instrumentation is the Chandra Proposers’ Observatory Guide. The POG is available from the CXC website (http://cxc.harvard.edu/proposer/POG/). Additional information can be found at the “Instruments and Calibration” (http://cxc.harvard.edu/cal/) link on the CXC web page.
A hardcopy version of the POG is available upon request to the CXC HelpDesk (http://cxc.harvard.edu/helpdesk/ ).
The CXC uses commercial Helpdesk software to track users’ requests and problems. Click on “Log into the CXC HelpDesk”, and the HelpDesk login box will appear. Enter a user name (we suggest first and middle initial followed by last name, but any unique string will be okay) and press enter/return to log in. No password is required. Once you have logged in, you can send a query (or “ticket”) by clicking on the “Submit Ticket” in the left-hand frame. New users are advised to enter their name, email address, and phone number (this only needs to be done once). HelpDesk also allows you to search previous tickets that are not private. More detailed information is given on the interface. Users can also email the CXC HelpDesk: cxchelp@head.cfa.harvard.edu.
In the last few days before and after the proposal deadline, we activate a dedicated email address for problems with proposal submission. This address should be used for proposal submission purposes only and is not active for most of the year. This dedicated email address helps the CDO to deal more efficiently with the very large volume of correspondence we receive around the proposal deadline. Dates for which the address is switched on will be posted on the proposer page at the CXC website. The proposal help email address is: prophelp@head.cfa.harvard.edu.
Proposal queries submitted via the HelpDesk interface and cxchelp email alias will always be answered.
ChaSeR (Search and Retrieval from the Chandra Data Archive) allows a user to check what observations have been made, what the status of the observations is (observed, publicly released, etc.), and ultimately to select data products and retrieve them. The web version of ChaSeR can be accessed at http://cda.harvard.edu:9011/chaser/mainEntry.do.
There is also a downloadable version of ChaSeR that has somewhat more sophisticated search capabilities than the web version. ChaSeR is available from the Chandra Data Archive (http://cxc.harvard.edu/cda/).
ChaSeR includes a precession tool and provides quick access to images. ChaSeR is extensively documented on the archive pages of the CXC website. In particular, there are detailed instructions for installations on many systems and a useful FAQ page. The user is referred to these sources for installation instructions as well as usage tips, updates, and more complete documentation.
The Target Pages (http://cxc.harvard.edu/targets/) is another tool that can be used to search the Chandra Data Archive (but not to download archival data). Detailed target lists can be found at http://cxc.harvard.edu/target_lists/index.html.
An additional tool of interest is the processing status tool, which provides detailed and comprehensive information about the processing of each observation. The processing status tool can be accessed via the Target Search Pages (click on the ObsID on the search results page). The tool can also be accessed from http://cxc.harvard.edu/soft/op/op_pst.html.
Instrument response functions (RMFs and ARFs) for simulating spectra within Sherpa and XSPEC can be found on the proposer page (http://cxc.harvard.edu/proposer/) and the Calibration Database (CALDB) page (http://cxc.harvard.edu/caldb/). These responses should be used for proposal preparation only; they should NOT be used for data analysis!
The CXC provides several software tools to aid in proposal preparation.
These tools perform the following functions:
All of these tools have web interfaces linked into the Proposer pages. Command-line (non-web) versions that have additional features are also available. For example, command line versions of Precess, Colden, Dates, and PIMMS allow for a list of input parameters in a text file. The web version of ObsVis gives target visibility and nominal roll angle as a function of time. The command-line version additionally shows instrument “footprints” on a Digital Sky Survey image.
The command-line versions of these tools are distributed with CIAO. Chandra users with CIAO installed can run these routines in the same way as all other CIAO tools (CLI tool names: prop_pimms, prop_colden, prop_dates, prop_precess, and obsvis). Standard CIAO helpfiles are available.
Helpfiles for proposal-related software and proposal “Threads” are available from the CXC proposer site (http://cxc.harvard.edu/proposer/ ). Helpfiles are available over the web as HTML files, in PDF format, and as part of the CIAO “ahelp” system. Proposal Threads are modeled on CIAO threads and give step-by-step examples of how to perform feasibility calculations, fill in RPS forms, and submit a proposal. They are intended primarily (but not exclusively) for less experienced Chandra users.
MARX is a suite of programs created by the MIT/CXC group and designed to enable the user to simulate the on-orbit performance of the Chandra X-ray Observatory. MARX provides a detailed ray-trace simulation of how Chandra responds to a variety of astrophysical sources and can generate standard FITS events files and images as output. It contains detailed models for the HRMA mirror system as well as the HETG and LETG gratings and all focal plane detectors. More detailed information, including the source code and documentation, is available from the MIT MARX Web Page (http://space.mit.edu/CXC/MARX/). MARX should be used to demonstrate the feasibility of challenging observations, for example resolving multiple or overlapping sources with unique spectra, HETG observations of extremely bright objects, or grating observations of extended sources.
CIAO is an extensive suite of tools designed for Chandra data reduction. Although not designed specifically for proposal preparation, CIAO can be used to analyze simulated Chandra data (e.g. from MARX) and create simulated spectra. Full details can be found at http://cxc.harvard.edu/ciao/. Sherpa is an interactive spatial/spectral fitting package that forms part of CIAO. It can also be used for simple simulations of Chandra spectra.
XSPEC is the spectral analysis portion of the Xanadu X-ray data analysis package, developed and maintained at NASA-GSFC. XSPEC can be obtained from http://heasarc.gsfc.nasa.gov/docs/xanadu/xspec/index.html.
The spectral simulation portion of XSPEC can also be run on-line. WEBSPEC can be accessed from http://heasarc.gsfc.nasa.gov/webspec/webspec.html.
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Center (CXC) is operated for NASA by the Smithsonian Astrophysical Observatory. 60 Garden Street, Cambridge, MA 02138 USA. Email: cxcweb@head.cfa.harvard.edu Smithsonian Institution, Copyright © 1998-2004. All rights reserved. |