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show_models xray.xspectral



show_models -- display the parameter values for all defined models




This tasks displays the input model descriptor in tabular form. It is normally used for debugging.


model = "" prompt = model descriptor or ? for help

This is a package wide parameter, found in the pkgpars parameter file.

The ASCII model descriptor. If "?" is input a short helpfile appears, and the model prompt reappears. A null string ("") will cause the previously determined best model to be taken from the file. Type help models_spectral from the CL for further information.

The spectral model descriptor is the sum of individual model components with the option of applying absoroption.

The general syntax for applying absorption to a component is:
    absorption(params) * component(params)

The general syntax for multiple model components is:
    abs(params) * compnt1(params) + abs(params) * compnt2(params) + ...

Possible components and arguments are:
powerlaw         log(normalization), energy index
bremsstrahlung   log(normalization), temperature [keV]
exponential      log(normalization), temperature [keV]
blackbody        log(normalization), temperature [keV]
raymond          log(normalization), temperature [keV], abundance table,
                                       abundance percent
line model       log(normalization), line-energy [keV],
                                       line-width [FWHM, in keV]

Absorption is applied as follows:
	absorption(galactic_NH (log))
	absorption(intrinsic_NH (log), redshift)
	absorption(galactic_NH (log), intrinsic_NH (log), redshift)

Unique abbreviations are recognized (e.g. pow). Parameters are specified by entering a single value (fixed) or a range (free) separated by ":". For free normalization of the first component, this parameter may be omitted. The normalization of a second component is linked to that of the first, other parameters may also be linked.
(pkgpars = "") [pset]

The name of the file containing the xspectral package wide parameters. If the name is null ("") then the parameters found for the pkgpars task will be used.


Display a sample two-component model:

xs> show_models
model descriptor or ? for help: abs(17)*ray(0.2:0.4 c 100)+ray(0.7 1:2 c 100)

Model: abs(17.00)*ray(0.20:0.40 cosmic 100.00)+ray(0.70 1.00:2.00 cosmic 100.00)

Model Component 1: Raymond Thermal
          Cosmic abundance at 100 percent.
          temperature = 0.300 (free)
 normalization (log) = 1.0000000 (calculated)
    galactic Nh (log) = 17.000 (fixed)
    intrinsic Nh (log) = 0.000 (fixed)
          redshift = 0.000 (fixed)

Model Component 2: Raymond Thermal
          Cosmic abundance at 100 percent.
          temperature = 1.500 (free)
 normalization (log) = 0.7000000 (fixed)
    galactic Nh (log) = 0.000 (fixed)
    intrinsic Nh (log) = 0.000 (fixed)
          redshift = 0.000 (fixed)


This task executes in less than 10 seconds.


For more information on the spectral model descriptor type help models_spectral at the cl.

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