CHANPHA [<XSPEC data file>] [<new data file>]
CHANPHA is the program to manipulate the contents of a PHA file.
The PHA file name can be given on the command line otherwise
you will be prompted for it. If the `new data file' name is not given a
new version of the old file is created. The default extension
for the file names is `.pha'. CHANPHA can be used e.g. to rebin the data
or to write the
names of the associated response, background and/or correction files into
the PHA file. These are then automatically used by XSPEC.