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To find and download HEASARC data in the cloud, you can use astroquery.heasarc or download our new tool, hark.

The HEASARC and NuSTAR teams are greatly saddened by the sudden passing of Katja Pottschmidt. Most recently Katja was the lead scientist for the NuSTAR Guest Observer Facility (GOF), a role she had supported for many years. During her science career she worked on many other high energy astrophysics missions and played an integral role in advancing our knowledge of the universe. She was a wonderful colleague and friend and will be keenly missed by all who knew her.

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Next: pexriv: reflected powerlaw, ionized Up: Additive Model Components Previous: pexmon: neutral Compton reflection   Contents


pexrav: reflected powerlaw, neutral medium

Exponentially cut off power law spectrum reflected from neutral material (Magdziarz & Zdziarski 1995). The output spectrum is the sum of the cut-off power law and the reflection component. The reflection component alone can be obtained for $rel_{refl} < 0$. Then the actual reflection normalization is $\vert rel_{refl}\vert$. Note that you need to then change the limits of $rel_{refl}$ to exclude 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 defined 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 PEXRAV_PRECISION eg xset PEXRAV_PRECISION 0.05. The default precision is 0.01 (ie 1%).

par1 $\Gamma$, first power law photon index, $N_E \propto E^{\Gamma}$
par2 $E_c$, cutoff energy (keV) (if $E_c$ = 0 there is no cutoff)
par3 $rel_{refl}$, reflection scaling factor (0 = no reflected component, <0 reflection component only)
par4 redshift, z
par5 abundance of elements heavier than He relative to the solar abundances
par6 iron abundance relative to that defined by abund
par7 cosine of inclination angle
norm photon flux at 1 keV (photons/keV/cm$^2$/s) of the cutoff broken power-law only (no reflection) in the observed frame.
next up previous contents
Next: pexriv: reflected powerlaw, ionized Up: Additive Model Components Previous: pexmon: neutral Compton reflection   Contents