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phosim_release / Output

PhoSim produces a stream of FITS files as its output in an identical fashion to a real telescope.

The files use the following conventions:

  • The files follow the standard astronomical FITS convention for images, and one file is produced for each readout amplifier.

  • The pixels are always organized in readout order (not necessarily related to the geometric orientation) and the values are given as unsigned integers or signed long integers (depending on the A/D system).

  • The FITS header contains basic FITS information, standard astronomical header information (e.g. WCS), and substantial simulation state information

  • The files have the naming convention {instrumentName}a{visitID}{instrumentConfiguration}{amplifierID}_{exposureID}.fits.gz

  • instrumentName is the name of the instrument being simulated (e.g. LSST), visitID is a number to name the exposure sequence, instrumentConfiguration (is a string containing essential information (most likely a filter configuration) (e.g. f2), amplifierID is the name of the amplifier (e.g. R22_S11_C13), and exposureID is the number of exposure in the sequence (e.g. E002)

  • A very useful optional output is the image of the electrons prior to readout. This is not possible with real telescopes (so use this with some caution), but lets the user to avoid routine bias/gain correction and amplifier reconstruction. This file has the naming convention: {instrumentName}e{visitID}{instrumentConfiguration}{chipID}_{exposureID}.fits.gz