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xset

set variables for XSPEC models

Modify a number of XSPEC internal switches.

Syntax: xset [abund |cosmo |delta |mdatadir |method |seed |statistic |usechainrule |weight |xsect |<string_name>] [ <options>|<string_value>]

The arguments abund, cosmo, method, statistic, weight, and xsect just run the appropriate XSPEC commands. mdatadir changes the directory in which XSPEC searches for model data files. You probably don't want to change this. The seed option requires an integer argument, which will then be used to immediately re-seed and re-initialize XSPEC's random-number generator.

The delta option is for setting fit delta values (see the newpar command) which are proportional to the current parameter value rather than fixed. For example,

XSPEC12> xset delta .15
will set each parameter fit delta to .15 * parVal. To turn proportional deltas off and restore the original fixed deltas, set delta to a negative value or 0.0. The current proportional delta setting can be seen with show control.

The usechainrule option can be used to switch between the fast (usechainrule yes) and slow (usechainrule no) options when calculating the derivatives of the fit statistic.

The <string_name> option can be used to pass string values to models. XSPEC maintains a database of <string_name>, <string_value> pairs created using this command. Individual model functions can then access this database. Note that xset does no checking on whether the <string_name> is used by any model so spelling errors will not be trapped.

To access the <string_name>, <string_value> database from within a model function use the fortran function fgmstr. This is defined as character*128 and takes a single argument, the string name as a character*128. If the <string_name> has not been set then a blank string will be returned.

The current <string_name> options, models to which they apply and brief descriptions are given in the following table :

APECROOT or SPEXROOT (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)expcheb6, (b)(v)(v)gadem, (v)mekal, mkcflow, nlapec, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Switch from default AtomDB or SPEX input files.
APECTHERMAL or SPEXTHERMAL (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)equil, (b)(v)expcheb6, (b)(v)(v)gadem, (b)(v)(v)gnei, (v)mekal, mkcflow, (b)(v)(v)nei, nlapec, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Thermally broaden emission lines in APEC or SPEX input files.
APECVELOCITY or SPEXVELOCITY (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)equil, (b)(v)expcheb6, (b)(v)(v)gadem, (b)(v)(v)gnei, (v)mekal, mkcflow, (b)(v)(v)nei, nlapec, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Velocity broaden emission lines in APEC or SPEX input files.
APECMINFLUX or SPEXMINFLUX (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)equil, (b)(v)expcheb6, (b)(v)(v)gadem, (b)(v)(v)gnei, (v)mekal, mkcflow, (b)(v)(v)nei, nlapec, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Set minimum flux for line broadening when using APEC or SPEX input files.
APECBROADPSEUDO or SPEXBROADPSEUDO (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)equil, (b)(v)expcheb6, (b)(v)(v)gadem, (b)(v)(v)gnei, (v)mekal, mkcflow, (b)(v)(v)nei, nlapec, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Broaden pseudo-continuum lines when using APEC or SPEX input files.
APECNOLINES or SPEXNOLINES (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)equil, (b)(v)expcheb6, (b)(v)(v)gadem, (b)(v)(v)gnei, (v)mekal, mkcflow, (b)(v)(v)nei, nlapec, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Continuum only when using APEC or SPEX input files.
APEC_TRACE_ABUND or SPEX_TRACE_ABUND (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)equil, (b)(v)expcheb6, (b)(v)(v)gadem, (b)(v)(v)gnei, (v)mekal, mkcflow, (b)(v)(v)nei, nlapec, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Set trace element abundances when using APEC or SPEX input files.
APECLOGINTERP or SPEXLOGINTERP (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)equil, (b)(v)expcheb6, (b)(v)(v)gadem, (b)(v)(v)gnei, (v)mekal, mkcflow, (b)(v)(v)nei, nlapec, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Use logarithmic interpolation between tabulated temperatures when using APEC or SPEX input files.
APECMULTITHREAD or SPEXMULTITHREAD (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)equil, (b)(v)expcheb6, (b)(v)(v)gadem, (b)(v)(v)gnei, (v)mekal, mkcflow, (b)(v)(v)nei, nlapec, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Parallelize over temperatures when calculating the lines in the spectrum using the APEC or SPEX input files.
APECEEBREMSS or SPEXEEBREMSS (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)equil, (b)(v)expcheb6, (b)(v)(v)gadem, (b)(v)(v)gnei, (v)mekal, mkcflow, (b)(v)(v)nei, nlapec, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Include calculation of the e-e bremsstrahlung when using the APEC or SPEX input files.
APECUSESPEX (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)(v)cie, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)expcheb6, (b)(v)(v)gadem, (v)mekal, mkcflow, nlapec, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Switch from APEC to SPEX input files but apply all other APEC settings.
APECUSENEI (b)(v)(v)apec, c6(v)mekl, c6p(v)mekl, ce(v)mkl, (b)(v)cempow, (b)(v)cheb6, (b)(v)coolflow, (b)(v)(v)dem, (b)(v)expcheb6, (b)(v)(v)gadem, (v)mekal, mkcflow, nlapec, (b)snapec, (b)(v)(v)tapec, rs(v)(v)apec, vmcflow Use NEI code to calculate CEI spectra.
APECEIGENFILE (b)(v)equil, (b)(v)(v)gnei, (b)(v)(v)nei, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov Switch from default AtomDB NEI eigenvector file.
NEIAPECROOT (b)(v)equil, (b)(v)(v)gnei, (b)(v)(v)nei, (b)(v)(v)npshock, (b)(v)(v)pshock, (b)(v)(v)rnei, (b)(v)(v)sedov Switch from default AtomDB NEI input files.
NSA_FILE nsa Change filename used for model data.
NSAGRAV_DIR nsagrav Change directory used for model data files.
NSMAX_DIR nsmax Change directory used for model data files.
NSMAXG_DIR nsmaxg Change directory used for model data files.
NSX_DIR nsx Change directory used for model data files.
POW_EMIN, POW_EMAX powerlaw, bknpower, bkn2pow, cutoffpl Switch to normalize to a flux calculated over an energy range.
CARBATM carbatm Switch the directory for the input file.
CFLOW_VERSION mkcflow, vmclow Switch CFLOW version number.
CFLOW_NTEMPS mkcflow, vmclow Switch number of temperature bins used in CFLOW model.
HATM hatm Switch the directory for the input file.
IREFLECT_MAX_E ireflect Set the maximum energy for which to calculate the output spectrum.
IREFLECT_PRECISION ireflect Set the fractional precision for the Greens' function adaptive integration.
REFLECT_MAX_E reflect Set the maximum energy for which to calculate the output spectrum.
REFLECT_PRECISION reflect Set the fractional precision for the Greens' function adaptive integration.
RFXCONV_DIR rfxconv directory to use for input model data files instead of the standard modelData directory.
RFXCONV_MAX_E rfxconv the maximum energy for which to calculate the output spectrum.
RFXCONV_PRECISION rfxconv precision used in adaptive Gauss-Kronrod quadrature of the Greens' function integral.
RGS_XSOURCE_FILE rgsext, rgsxsrc set the file from which to read the image filename, boresight and extraction information.
SUZPSF-IMAGE suzpsf Set image file to be used for surface brightness.
SUZPSF-RA suzpsf Set RA for center surface brightness map which is taken from the WMAP.
SUZPSF-DEC suzpsf Set Dec for center surface brightness map which is taken from the WMAP.
SUZPSF-MIXFACT-IFILE# suzpsf Set filename to read mixing factors.
SUZSF-MIXFACT-OFILE# suzpsf Set filename to write mixing factors.
XILCONV_MAX_E xilconv maximum energy for which to calculate the output spectrum.
XILCONV_PRECISION xilconv precision used in adaptive Gauss-Kronrod quadrature of Greens' function integral.
XILCONV_DIR xilconv directory to use for ionization model filenames instead of the standard modelData directory.
XILCONV_VERSION xilconv version number of the xillver file, options are 3 and 5 (the default).
XMMPSF-IMAGE xmmpsf Set image file to be used for surface brightness.
XMMPSF-RA xmmpsf Set RA for center surface brightness map which is taken from the WMAP.
XMMPSF-DEC xmmpsf Set Dec for center surface brightness map which is taken from the WMAP.
XMMPSF-MIXFACT-IFILE# xmmpsf Set filename to read mixing factors.
XMMPSF-MIXFACT-OFILE# xmmpsf Set filename to write mixing factors.
XSCAT_DIR xscat Change directory used for model data files.
ZXIPCF_DIR zxipcf Change directory used for model data files.

Examples:

XSPEC12> xset NEIAPECROOT 2.0
   // Set the NEIAPECROOT variable to 2.0
XSPEC12> xset 
   // List the current string variables
XSPEC12> xset apecroot /foo/bar/apec_v1.01
   // Set the APECROOT variable
XSPEC12> xset seed 1515151
   // Re-initialize the pseudo random-number generator
   // with the seed value 1515151