psf_table format

This is a PSF FITS format we agree on for IACTs. This file contains the offset- and energy-dependent table distribution of the PSF.

This format is almost identical to the OGIP radial PSF format. The differences are that we don’t have the dependency on azimuthal field of view position and the units are different.

Columns:

• RAD_LO, RAD_HI – ndim: 1, unit: deg

  • Offset angle from source position

• THETA_LO, THETA_HI – ndim: 1, unit: deg

  • Field of view offset axis

• ENERG_LO, ENERG_HI – ndim: 1, unit: TeV

  • Energy axis

• RPSF – ndim: 3, unit: deg^-2

  • Point spread function value \(dP/d\Omega\), see Probability distributions.

Recommended axis order: RAD, THETA, ENERGY.

Header keywords: none