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bexrav: reflected e-folded broken power law, neutral medium

A broken power-law spectrum multiplied by exponential high-energy cutoff, exp(-E/Ec), and reflected from neutral material. See Magdziarz & Zdziarski (1995) for details.

The output spectrum is the sum of an e-folded broken power law and the reflection component. The reflection component alone can be obtained for $\vert rel_{refl}\vert < 0$. Then the actual reflection normalization is $\vert rel_{refl}\vert$. Note that you need to change then the limits of $\vert rel_{refl}\vert$ excluding zero (as then the direct component appears). If $E_c = 0$, there is no cutoff in the power law. The metal and iron abundance are variable with respect to those set by the command abund. The opacities are those set by the command xsect. As expected in AGNs, H and He are assumed to be fully ionized.

The core of this model is a Greens' function integration with one numerical integral performed for each model energy. The numerical integration is done using an adaptive method which continues until a given estimated fractional precision is reached. The precision can be changed by setting BEXRAV_PRECISION eg xset BEXRAV_PRECISION 0.05. The default precision is 0.01 (ie 1%).

par1 $\Gamma_1$, first power law photon index
par2 $E_{break}$, break energy (keV)
par3 $\Gamma_2$, second power law photon index
par4 $E_c$, the e-folding energy in keV (if $E_c = 0$ there is no cutoff)
par5 $rel_{refl}$, reflection scaling factor (1 for isotropic source above disk)
par6 cosine of inclination angle
par7 abundance of elements heavier than He relative to the solar abundances
par8 iron abundance relative to the above
par9 $z$, redshift
norm photon flux at 1 keV of the cutoff broken power-law only (no reflection) in the observed frame.

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Last modified: Friday, 23-Aug-2024 13:20:40 EDT

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.