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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.
next up previous contents
Next: pexrav: reflected powerlaw, neutral Up: Additive Model Components Previous: pegpwrlw: power law, pegged   Contents