Yaxx (Yet Another X-ray Xtractor) is a Perl script that facilitates batch spectral processing of Chandra data using CIAO tools, Sherpa, S-lang, and Perl open source software. It includes automated spectral extraction, fitting, and report generation. The primary emphasis is on having a simple tool that can be run without requiring an extensive learning curve. The simplest task of fitting a default model to a single source in a field requires only three steps: copy the Chandra data into an appropriate directory, create a two-line file specifying the ObsId and source position, and run yaxx. However, for those with the motivation, yaxx is highly configurable and can be customized to support complex analysis. In particular yaxx uses template files and takes full advantage of the unique Sherpa / S-lang environment to make much of the processing user configurable.

The basic analysis flow using yaxx is:

Presently Yaxx supports Linux and Solaris 2.8 platforms. It is expected that support for Mac OS X will be added pending a CIAO tool bug fix.

Yaxx has been developed by Tom Aldcroft with support from NASA under NASA grant NAS8-39073 and CXC archival research grant AR2-3009X (ChaMP collaboration).

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Copyright (C) 2006 by the Smithsonian Astrophysical Observatory.