The Fermi telescope was launched in June 2008 and has a Gamma-Ray Burst monitor (GBM) and a Large Area Telescope (LAT). Kim Tolbert leads a NASA GI program to make the Fermi data available for the solar community.

She has a webpage at:


that describes how to use the software. 

There are two types of Fermi data: CSPEC and CTIME. The former has 128 energy channels and 4.096 or 1.024 s time resolution. The latter have 8 energy channels and 0.256 or 0.064 s time resolution. There are multiple detectors pointing in different directions. The OSPEX software automatically selects the detector pointing closest to the Sun, although for large flares pile-up may occur, making other detectors more suitable.

Downloading files

Fermi files can be downloaded through the ospex browser. There doesn't seem to be an environment variable for pointing to the location of the files.

Downloading files for one period gives rise to two types of file: PHA and RSP or RSP2. The latter are response files, the former the data files. OSPEX automatically chooses (and downloads) the four detectors pointingclosest to the Sun.

The OSPEX team automatically process all Fermi data for solar flares, and so it's best to choose your particular flare in the GUI, and the correct files will be downloaded.

Plotting data

I wasn't successful in being able to make a plot from the command line so I had to use the GUI to create a .eps file instead. The command line plots had strange structure in them, which was different to the GUI plots. Note that there's a "write script" option in the GUI which is supposed to allow you to reproduce the GUI plot.