The ASTERIX psf system is used by instrument independent applications requiring access to point spread function information, which is inherently instrument specific. The psf uses three ADAM parameters, PSF, MASK and AUX, although not all three are needed by all psfs. The PSF parameter is the most important, controlling the psf to be used,
PSF system options :
ANAL EXOLE PWFC TABULAR WFC
XRT_HRI XRT_PSPC
POLAR(psf,rbin[,abin]) RECT(psf,xbin[,ybin])
PSF - Choose PSF to use for source model /'WFC'/ >
Note that the exact prompt displayed with PSF may vary from
application to application, as the use to which the data is to be put
may also vary. The seven lines preceding the prompt show the options
available in the psf system, in two groups. The first group contains
the primitive psf names, ANAL, EXOLE and so on. These
are the names of instrument psfs plus TABULAR and ANAL.
To invoke one of this group, simply enter its name at the PSF
prompt. A default may be supplied if the dataset was produced by an
ASTERIX instrument interface or the event simulator, EVSIM.
The second group shows the allowed syntax for psf model specifications.