Last modified: December 2018

URL: http://cxc.harvard.edu/sherpa/ahelp/xspexriv.html
AHELP for CIAO 4.11 Sherpa v1

xspexriv

Context: models

Synopsis

The XSPEC pexriv model: reflected powerlaw, neutral medium.

Syntax

xspexriv

The xspexriv model is an additive model component.

Description

The model is described at [1] .


Example

>>> create_model_component("xspexriv", "mdl")
>>> print(mdl)

Create a component of the xspexriv model and display its default parameters. The output is:

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.PhoIndex thawed            2           -9            9           
   mdl.foldE    thawed          100            1        1e+06        keV
   mdl.rel_refl thawed            0            0        1e+06           
   mdl.redshift frozen            0       -0.999           10           
   mdl.abund    frozen            1            0        1e+06           
   mdl.Fe_abund frozen            1            0        1e+06           
   mdl.cosIncl  frozen         0.45         0.05         0.95           
   mdl.T_disk   frozen        30000        10000        1e+06          K
   mdl.xi       thawed            1            0         1000   erg cm/s
   mdl.norm     thawed            1            0        1e+24           

ATTRIBUTES

The attributes for this object are:

PhoIndex

The first power-law photon index.

foldE

The cut-off energy (E_c) in keV. Set to 0 for no cut off.

rel_refl

The reflection scaling parameter (a value between 0 and 1 for an isotropic source above the disk, less than 0 for no reflected component).

redshift

The redshift of the source.

abund

The abundance of the elements heaver than He relative to their solar abundance, as set by the set_xsabund function.

Fe_abund

The iron abundance relative to the solar abundance, as set by the set_xsabund function.

cosIncl

The cosine of the inclination angle in degrees.

T_disk

The disk temperature in K.

xi

The disk ionization parameter: see [1] for more details.

norm

The normalization of the model: see [1] for an explanation of the units.

Notes

The precision of the numerical integration can be changed by using the set_xsxset function to set the value of the PEXRIV_PRECISION keyword, which defines the fractional precision. The default is 0.01 (1%).

References

XSPEC version

CIAO 4.11 comes with support for version 12.10.0e of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;
print(xspec.get_xsversion())'
12.10.0e

Bugs

See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.

See Also

models
xspexmon, xspexrav