COMPPS model computes Comptonization spectra is different geometries using exact numerical solution of the radiative transfer equation. The computational "iterative scattering method" is similar to the standard Lambda-iteration and is described in Poutanen J., Svensson R., 1996, ApJ, 470, 249 (PS96). This model has been incorporated to XSPEC 12 as a standard model.

Readme file


Atmosphere model for X-ray bursting neutron star accounting for Compton scattering using relativistic kinetic equation and exact redistribution function.
If you use the model for the data analysis, please, refer to
Suleimanov V. et al. 2011, A&A, 527, A139
Suleimanov V. et al. 2012, A&A, 545, A120

Theoretical spectra of X-ray bursting neutron star (NS) model atmospheres are widely used for determination of the NS basic parameters such as their masses and radii. Compton scattering, that plays an important role in spectra formation at high luminosities, is often accounted for using the differential Kompaneets operator, while in other models a more general, integral operator for the Compton scattering kernel is used. We construct here accurate NS atmosphere models using exact treatment of Compton scattering with the integral relativistic kinetic equation and exact relativistic angle-dependent redistribution function.

Readme file
Xspec model file
Set parameters
Atmosphere model spectra (fluxes)
lmodel_burstatmo.dat, to be copied to lmodel.dat file