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Xspec: An X-Ray Spectral Fitting Package

Version 12.15.0 Now Available

Helpful information available includes:

• Download and installation instructions
• Xspec release notes
• Getting Help
• Xspec internal functions guide
• Xspec facebook group [external]
• External Resources
• Historical Xspec information

The latest Xspec reference is Arnaud, K.A., 1996, Astronomical Data Analysis Software and Systems V, eds. Jacoby G. and Barnes J., p17, ASP Conf. Series volume 101.

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Xspec 12 was developed by: Keith Arnaud, Ben Dorman, and Craig Gordon
HEASARC Software Development, Astrophysics Science Divsion
Code 660.1, NASA/GSFC, Greenbelt MD 20771

Please send comments, questions, and bug reports to xspechelp@athena.gsfc.nasa.gov