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pexriv: reflected powerlaw, ionized medium

Exponentially cut off power law spectrum reflected from ionized material (Magdziarz & Zdziarski MNRAS, 273, 837; 1995). Ionization and opacities of the reflecting medium is computed as in the absori model. The output spectrum is the sum of the cutoff power law and the reflection component. The reflection component alone can be obtained for . Then the actual reflection normalization is . Note that you need to change then the limits of excluding zero (as then the direct component appears). If Ec = 0 there is no cutoff in the power law. The metal and iron abundances are variable with respect to those defined by the command abund.

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 PEXRIV_PRECISION eg xset PEXRIV_PRECISION 0.05. The default precision is 0.01 (ie 1%).

par1

, first power law photon index,

par2

Ec, cutoff energy (keV) (if Ec = 0 there is no cutoff)

par3

relrefl, reflection scaling factor (0, no reflected component < relrefl < 1 for isotropic source above disk)

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

par8

disk temperature in K

par9

disk ionization parameter, , where Fion is the 5eV 20keV irradiating flux, n is the density of the reflector; see Done et al., 1992, ApJ, 395, 275.

norm

photon flux at 1 keV (photons keV1cm-2 s-1) of the cutoff broken power-law only (no reflection) in the observed frame.

 

 

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