hatm: Nonmagnetic hydrogen atmosphere of a neutron star
This model provides the spectra emitted from a nonmagnetic hydrogen
atmosphere of a neutron star. The model spectra in a 0  20 keV range
of (unredshifted) photon energy are computed on a grid of surface
gravity accelerations log(g)=13.7  14.9 (in cgs units) and effective
temperatures T = 0.5  10 MK. For a given set of the fitting
parameters, the surface gravity g and the gravitational redshift z are
derived from the mass M and radius R of the star. The trial spectra
are computed using a linear interpolation between the nearest model
spectra on the Tlog(g) grid, and the boundaries of the energy bins
and the number of photons in each bin are divided by (1+z). The
details of the model can be found in Suleimanov et al. (2017)
and Klochkov et
al. (2015).
The directory used for the files required by this model can be changed
by using the xset command to set HATM.
The parameters are:
par1 
Effective temperature T (MK) 
par2 
Neutron star mass M (M) 
par3 
Neutron star radius R (km) 
par4 
Normalization K = A/(dkpc) where dkpc is the distance to the source in units of 10 kpc and A characterizes the fraction of the surface emitting the radiation (A=1 corresponds to the case when the radiation is emitted from the entire surface). 
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Last modified: Tuesday, 28May2024 10:09:22 EDT
