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pexmon: neutral Compton reflection with self-consistent Fe and Ni lines.

This model from Nandra et al. (2007) combines pexrav with self-consistently generated Fe K$\alpha$, Fe K$\beta$, Ni K$\alpha$ and the Fe K$\alpha$ Compton shoulder. Line strengths are based on Monte Carlo calculations by George & Fabian (1991) which are parametrized for $1.1 < \gamma < 2.5$ by :

$\displaystyle EW = 9.66 EW_0(\gamma^{-2.8} - 0.56) $

with inclination dependence for $i < 85$ degrees :

$\displaystyle EW = EW_0 (2.20 \cos i - 1.749 (\cos i)^2 + 0.541(\cos i)^3) $

and abundance dependence :

$\displaystyle \log EW = \log EW_0 (0.0641 \log A_{Fe} - 0.172 (\log A_{Fe})^2) $

The Fe K$\beta$ and Ni K$\alpha$ line fluxes are 11.3% and 5% respectively of that for Fe K$\alpha$. The Fe K$\alpha$ Compton shoulder is approximated as a gaussian with E = 6.315 keV and $\sigma = 0.035$ keV. The inclination dependence is taken from Matt (2002) such that :

$\displaystyle EW_{shoulder} = EW_{Fe K\alpha}(0.1 + 0.1 \cos i) $

The model parameters are :

par1 $\gamma$, power-law photon index, $N_E \propto E^{-\gamma}$.
par2 $E_c$, cutoff energy in keV (if $E_c$ = 0 there is no cutoff).
par3 scale, the scaling factor for reflection; <0 = no direct component, 1 = isotropic source above the disk
par4 $z$, redshift
par5 $A$, abundance of elements heavier than He relative to Solar.
par6 $A_{fe}$, iron abundance relative to Solar.
par7 the inclination angle (degrees).
norm normalization is the photon flux at 1 keV (photons/keV/cm$^2$/s) of the cutoff power law only (without reflection) and in the Earth frame.
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HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.