Version 11.2 Changes

The following list summarizes, for reference, the major changes to XSPEC from version 11.1 to 11.2.

• Commands

  $\rightarrow$

  There is a new command : xset. This is a wrap-up for abund, cosmo, mdatadir, method, statistic, weight, xsect. It also enables the setting of strings to be passed to models.

  Those currently implemented are :

  APECROOT	which allows the user to change the APEC input files used
  	in the models apec and vapec
  NEIVERS	the version number for the NEI models
  NEIAPECROOT	which allows the user to change the NEIAPEC input files
  	used in the NEI models when NEIVERS=2.0.
  RGS_XSOURCE_FILE	the file to read to get rgsxsrc parameters.

  Note that xset does not check whether the names or strings input are valid. To use this facility for local models all you need to do is add a call to fgmstr(name) to your routine (both fgmstr and name should be declared as character*128).

  $\rightarrow$

  The eqwidth, flux, and lumin commands now have an option to estimate a confidence range. A similar technique is used to improve the goodness command.

  $\rightarrow$

  The fakeit command now automatically creates a faked background file to go with the faked source file if a background file is in use when the command is run. If the source file is called foo.bar then the background file is foo_bkg.bar.

  $\rightarrow$

  setplot rebin has an option to change the algorithm used to calculate error bars in plots.

  $\rightarrow$

  setplot id has an option to set a redshift.

  $\rightarrow$

  abund (and xset abund) now also include the wilm relative abundances (from Wilm et al 2000 and appropriate for the ISM).

• Models

  $\rightarrow$

  The NEI models now come in several versions. To switch between them use eg xset neivers 1.0. 1.0 gives the NEI models in XSPEC v11.1, 1.1 uses improved eigenfunction files, and 2.0 uses the improved eigenfunction files and emission spectra calculated using APEC. Emission from Ar is included in version 2.0.

  $\rightarrow$

  A new model rgsxsrc is useful for analyzing XMM-Newton RGS spectra of extended sources.

  $\rightarrow$

  The pile-up model has additional parameters for PSF fraction and number of regions. It should now be an exact analog of that available in ISIS.

• General

  $\rightarrow$

  Since the Minuit source code is now freely distributable it is included in this version of XSPEC. It is no longer necessary to download an additional library in order to use the minuit options.

  $\rightarrow$

  An inefficiency in reading response matrices has been removed. They now read up to five times faster than in v11.1.

  $\rightarrow$

  During a fit only the variable parameters are written out instead of all the parameters.