Last modified: December 2023

URL: https://cxc.cfa.harvard.edu/sherpa/ahelp/xsnsa.html
AHELP for CIAO 4.16 Sherpa

xsnsa

Context: models

Synopsis

The XSPEC nsa model: neutron star atmosphere.

Syntax

xsnsa

The xsnsa model is an additive model component.

Description

The model is described at [1] .


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.LogT_eff thawed            6            5            7          K
   mdl.M_ns     thawed          1.4          0.5          2.5       Msun
   mdl.R_ns     thawed           10            5           20         km
   mdl.MagField frozen            0            0        5e+13          G
   mdl.norm     thawed            1            0        1e+24           

ATTRIBUTES

The attributes for this object are:

Attribute Definition
LogT_eff The log of Teff, the unredshifted effective temperature.
M_ns The neutron star gravitational mass, in units of the solar mass.
R_ns The neutron star radius, in km.
MagField The neutron star magnetic field strength, in Gauss. It must be fixed at one of 0, 1e12, or 1e13 G.
norm The normalization is 1/D^2, where D is the distance to the neutron star in pc.

References

XSPEC version

CIAO 4.16 comes with support for version 12.13.1e of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;
print(xspec.get_xsversion())'
12.13.1e

Bugs

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

See Also

models
xsnsagrav