Read in one or more auxiliary response files (ARF). An ARF gives area versus
energy and is used to modify the response matrix for a data set. The file must
be in the OGIP standard format.
XSPEC> arf [<filespec>...]
where <filespec> =:: [<data set num>] <file name>...
and where <file name> is the name of the auxiliary response file to be used
for the response of the associated data set. <data set num> is the data set
number for the first <filename> in the specification, <data set num>+1 is
the data set number for the next file, and so on. If no <data set num> is given
in the first <filespec> it is assumed to be 1. If no file specifications are
entered, then none of the data set responses are modified. An error message is
printed if the data set number is greater than the current number of data sets
(as determined from the last use of the data command). A file name none
indicates that no auxiliary response is to be used for that data set. No auxiliary
response
means that any incident spectrum will produce no counts for those particular channels.
If a file is not found or cannot be opened for input, then the user is prompted
for a replacement auxiliary response file. An <EOF> at this point is equivalent
to none. See the data command for ways to totally remove the data set from
consideration.