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NOTE: Most of the High Level Science Products are unavailable while unscheduled maintenance is being performed. They will be incrementally restored over the course of this week. We apologize for any inconvenience.

HUT Extraction Software

Standard FITS I/O Software

The various FITS files from HUT (idf.fits, cal.fits, and tv.fits) can all be read by any standard FITS I/O library. A summary of some of the most popular ones can be found here.

As a very quick example, here are a few lines that demonstrate how to read the night-only spectrum for an observation of Z-CAM. This assumes you've already downloaded the FITS files.

;; Specify the file to read.
file = "HUT224401cal.fits"

;; Read in HDU2, the second extension, which contains the night-only spectrum.
;; We make use of the Goddard Astronomy Library function MRDFITS.
;; The return value is an IDL structure when the extension is a binary fits table.
fits_exten2_data = MRDFITS(file, 2, fits_exten2_hdr, /SILENT)

;; Create variables that store the wavelength and flux in 1-D arrays.
wls = fits_exten2_data.wave
fls = fits_exten2_data.flux

;; Plot the spectrum.

C Routines Provided By HUT Team

The HUT team has also provided a set of C routines to read in the idf.fits files and create cal.fits files. This can be useful if, for example, you wish to modify the inclusion/exclusion of particular photons to re-create a new spectrum. The package can be downloaded here in a gzipped tarball, which contains the necessary C program files, Makefile, and README.