Keyword Position Type Description
------- -------- ---- -----------
OFFAX 1 REAL OFF-axis angle (arcminutes)
ENERGY 2 REAL Mean photon energy (keV)
PFRAC 3 REAL Fraction of counts wanted (e.g. 0.9)
DISP LOGICAL Display the result on the screen ?
PSFRAD REAL Output parameter containing the
90% radius in DEGREES.