Robert C. Byrd Green Bank Telescope
NRAO Green Bank
Langston, Garwood, Prestage, Clark, Shelton and Hunt
March 8th, 2007
GBT Software Project Note 5.5
The FITS format structure is presented for the GBT spectrometer
scan data files. The scan data FITS files are permanently
archived after each observation, and will usually be input to the
aips++ filler, which has the task of combining all scan data FITS
files into an aips++ Measurement Set. This data may then either be
processed further in aips++, or written out in an aips++ supported
FITS format (one of which is single dish FITS).
The scan data FITS files contain both 1) a complete description of
the spectrometer setup for the observation and 2) measurement data
with a FITS keyword description of the data organization. The
ACT_STATE, PORT, STATE and SAMPLER tables describe the setup and
the DATA table contains measured values.
- 8th November 2001
- Penultimate definition of FITSVER 1.1; released
for general comment (Richard Prestage).
- 16th November 2001
- Final version agreed for implementation of
FITSVER 1.1. No changes c.f. 8th November 2001 version. Subsequent
changes to the content of this document should increment the document
version number (Richard Prestage).
- 28th November 2001
- Revised comment in PHDU section for DATE-OBS,
- 14th March 2002
- Corrected description of ACT_STATE table (Mark Clark).
- 27th June 2002
- Modifications for FITSVER 1.2. The polarity
of the active switching signals in the ACT_STATE were reversed
in previous versions (Mark Clark).
OBJECT, PROJID, OBSID, and SCAN (Amy Shelton).
- 8th March 2007
- Bug fix for FITSVER 2.3.
The INTEGRAT column in DATA was being incorrectly written in
column-dominant fashion when it should have been written in
row-dominant fashion (John Ford, Melinda Mello, Mark Clark).