This page contains links to documents that define the recommended FITS formats for various types of data files used within High Energy Astrophysics. The first section lists the higher-level definition documents, and the second sections lists the 15 specific recommendations that were approved by the HEASARC FITS Working Group.

I. General HEASARC FITS Documents

• Event Lists Definition and File Format. (also available in postscript and latex format).
  A list of recommended columns and keywords in an Event List has also been published in Legacy 6, 36 (1995).
• Spectral analysis FITS file formats for Xspec-compatible PHA files. See also the Addendum.
• Definition of RMF and ARF Spectral calibration file formats. See also the Addendum.
• XSPEC Table Models file format
• WMAP FITS file format in spectral files
• Timing analysis data file formats for High Energy Astrophysics Data
• Effective Areas FITS file format
• Radial PSF datasets FITS file format
• 2D (image) PSF datasets FITS file format
• Vignetting Functions FITS file format
• Strings for specifying Physical Units within FITS files
• Standard Strings for Mission, Instrument, Filter, Detector & Grating Names for OGIP FITS files
• Standard strings for Detector Operating and Observing Modes. (Also available in postscript and latex format).
• Table Indexing - A Proposal for creating indices on FITS tables (Postscript)
• Calibration Database: documentation on installation and use of the CALDB.

II. Specific HEASARC Recommendations

The following 15 specific recommendations were formally approved by the HEASARC FITS Working Group from 1993 through 1995.

• R1: Recommends using underscores rather than hyphens in FITS keywords and column names (text version)
• R3: RA and Dec keywords for giving the position of the observed object, the telescope pointing, and the spacecraft axes (text version)
• R4: The CATIDn FITS keywords to contain source catalog identifications (text version)
• R5: Specifying physical units in FITS files. This recommendation is contained in OGIP memo ogip_93_001 (postscript, latex). A slightly earlier version of this memo was published in Legacy 4, 57 (1994).
• R6: On using the TLMINn, TLMAXn, TDMINn and TDMAXn keywords to record the the minimum and maximum values within columns of FITS tables (text version)
• R7: The CREATOR keyword to denote the name and version of the software program that generated that FITS file/extension (text version)
• R2/R8: The HDUCLASn/HDUVERS keywords to provide a hierarchial classification scheme for the various types of FITS extensions (text version). Also available is a list of all HDUCLASn/HDUVERS values currently defined by the HFWG.
• R9: Quality flags with a value of zero should be reserved to indicate GOOD (not rejected) quality data. Non-zero quality flag values may be used to indicate varying degrees of 'badness'. (text version)
• R10: Keywords to define channel & energy boundaries (text version)
• R11: Keywords and definitions relating to exposure times (text version)
• R12: Standard strings to denote the mission, instrument and filters within X- and gamma-ray astronomy. This recommendation is contained in OGIP memo ogip_93_013 (postscript, latex).
• R13: Long string keyword convention (text version)
• R14: TSORTKEY - a keyword for specifying the sort order of a FITS Table (text version)
• R15: Recommendations for naming columns in a FITS table (text, latex, postscript)