Creating FITS format files for XSPEC
RMF files
The definition of the FITS format for response matrix files can be
found in the OGIP document
CAL/GEN/92-002 with modifications in
CAL/GEN/92-002a. The format comprises a primary header and two
binary table extensions. There are routines available in the FTOOLS
CALLIB subroutine library which can be used to create
the binary table extensions. These are :
These routines can be found in the
FTOOLS distribution in the directory callib/src/gen.
The RSP_MATRIX extension stores the matrix in a compressed format described
in
CAL/GEN/92-002. An example subroutine, cmprsp,
shows how this compressed format is generated from a standard matrix.
Another example subroutine shows how to
create the RMF fits file and attach the EBOUNDS and RSP_MATRIX extensions
using the
CALLIB routines.
ARF files
The definition of the FITS format for the ancillary response file can be
found in the OGIP document
CAL/GEN/92-002 with modifications in
CAL/GEN/92-002a. The format comprises a primary header and a
binary table extension. The SPECRESP binary table extension can be
created by the routine wtarf1.f in the FTOOLS
CALLIB subroutine library. This routine can be found in the
FTOOLS distribution in the directory callib/src/gen.
Spectral files
The definition of the FITS format for the spectral file can be
found in the OGIP document
OGIP/92-007. The format comprises a primary header and a
binary table extension. The SPECTRUM binary table extension can be created
using the routine wtpha2.f in the FTOOLS
CALLIB subroutine library. This routine can be found in the
FTOOLS distribution in the directory callib/src/gen. The routine
wt_spec.f in the same directory provides an
example use of wtpha2.
Linking to the required libraries
To use the routines described above you need to have an installed copy of
the core
FTOOLS distribution, including the libraries libcaltools.a, libftools.a,
and libfitsio.a. The link line in the makefile should include :
-L$FTOOLS/lib -lcaltools -lxanlib -lftools -lfitsio
where $FTOOLS is the top level system-dependent directory of the
installed ftools.