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Last modified: December 2015

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AHELP for CIAO 4.9 Sherpa v1


Context: models


Pair plasma model. XSPEC model.


A nonthermal pair plasma model based on that of Lightman and Zdziarski (1987, ApJ 319, 643) from Magdziarz and Zdziarski. It includes angle-dependent reflection from Magdziarz and Zdziarski (1995, MNRAS 273, 837). In versions 1.1 and above the Compton reflection is done through an internal call to the reflct model. The Greens' function integration required for the Compton reflection calculation is performed to an accuracy of 0.01 (i.e. 1%). This can be changed using, e.g.,

sherpa> set_xsxset('NTEEA_PRECISION', '0.05')

The abundances are set up by the set_xsabund command.

This is an additive model component.

xsnteea Parameters

Number Name Description
1 l_nth nonthermal electron compactness
2 l_bb blackbody compactness
3 f_refl scaling factor for reflection; 1 = isotropic source above disk
4 kT_bb blackbody temperature in eV
5 g_max the maximum Lorentz factor
6 l_th thermal compactness; 0 = pure nonthermal plasma
7 tau_p Thomson optical depth of ionization electrons (e.g. 0)
8 G_inj electron injection index; 0 = monoenergetic injection
9 g_min minimum Lorentz factor of the power law injection; not used for monoenergetic injection
10 g_0 minimum Lorentz factor for nonthermal reprocessing; 1 < g_0 <= gmin
11 radius radius in cm (for Coulomb/bremsstrahlung only)
12 pair_esc pair escape rate in c; 0 <= paires <= 1, see Zdziarski 1985, ApJ, 289, 514
13 cosIncl cosine of inclination angle
14 Fe_abund iron abundance relative to that defined by set_xsabund
15 redshift redshift, z
16 norm photon flux of the direct component without reflection at 1 keV in the observer's frame.

XSPEC version

This information is taken from the XSPEC User's Guide. Version 12.9.0o of the XSPEC models is supplied with CIAO 4.9.


For a list of known bugs and issues with the XSPEC models, please visit the XSPEC bugs page.

To check the X-Spec version used by Sherpa, use the get_xsversion routine from the xspec module:

sherpa> from sherpa.astro.xspec import get_xsversion
sherpa> get_xsversion()

See Also

absorptionedge, absorptiongaussian, absorptionlorentz, absorptionvoigt, accretiondisk, atten, bbody, bbodyfreq, beta1d, beta2d, blackbody, box1d, box2d, bpl1d, bremsstrahlung, brokenpowerlaw, ccm, const1d, const2d, cos, delta1d, delta2d, dered, devaucouleurs2d, disk2d, edge, emissiongaussian, emissionlorentz, emissionvoigt, erf, erfc, exp, exp10, fm, gauss1d, gauss2d, hubblereynolds, jdpileup, linebroad, list_model_components, list_models, lmc, load_xscflux, load_xsgsmooth, load_xsireflect, load_xskdblur, load_xskdblur2, load_xskerrconv, load_xslsmooth, load_xspartcov, load_xsrdblur, load_xsreflect, load_xssimpl, load_xszashift, load_xszmshift, log, log10, logabsorption, logemission, logparabola, lorentz1d, lorentz2d, models, normbeta1d, normgauss1d, normgauss2d, opticalgaussian, poisson, polynom1d, polynom2d, polynomial, powerlaw, powlaw1d, recombination, scale1d, scale2d, schechter, seaton, sersic2d, shell2d, sigmagauss2d, sin, sm, smc, sqrt, stephi1d, steplo1d, tablemodel, tan, xgal, xs, xsabsori, xsacisabs, xsagauss, xsapec, xsbapec, xsbbody, xsbbodyrad, xsbexrav, xsbexriv, xsbkn2pow, xsbknpower, xsbmc, xsbremss, xsbvapec, xsbvvapec, xsc6mekl, xsc6pmekl, xsc6pvmkl, xsc6vmekl, xscabs, xscemekl, xscevmkl, xscflow, xscompbb, xscompls, xscompmag, xscompps, xscompst, xscomptb, xscompth, xscomptt, xsconstant, xsconvolve, xscplinear, xscutoffpl, xscyclabs, xsdisk, xsdiskbb, xsdiskir, xsdiskline, xsdiskm, xsdisko, xsdiskpbb, xsdiskpn, xsdust, xsedge, xseplogpar, xseqpair, xseqtherm, xsequil, xsexpabs, xsexpdec, xsexpfac, xsezdiskbb, xsgabs, xsgadem, xsgaussian, xsgnei, xsgrad, xsgrbm, xsheilin, xshighecut, xshrefl, xskerrbb, xskerrd, xskerrdisk, xslaor, xslaor2, xslogpar, xslorentz, xslyman, xsmeka, xsmekal, xsmkcflow, xsnei, xsnotch, xsnpshock, xsnsa, xsnsagrav, xsnsatmos, xsnsmax, xsnsmaxg, xsnsx, xsnthcomp, xsoptxagn, xsoptxagnf, xspcfabs, xspegpwrlw, xspexmon, xspexrav, xspexriv, xsphabs, xsplabs, xsplcabs, xsposm, xspowerlaw, xspshock, xspwab, xsraymond, xsredden, xsredge, xsrefsch, xsrnei, xssedov, xssirf, xssmedge, xsspexpcut, xsspline, xssrcut, xssresc, xssss_ice, xsstep, xsswind1, xstbabs, xstbgrain, xstbvarabs, xsuvred, xsvapec, xsvarabs, xsvbremss, xsvequil, xsvgadem, xsvgnei, xsvmcflow, xsvmeka, xsvmekal, xsvnei, xsvnpshock, xsvphabs, xsvpshock, xsvraymond, xsvrnei, xsvsedov, xsvvapec, xsvvgnei, xsvvnei, xsvvnpshock, xsvvpshock, xsvvrnei, xsvvsedov, xswabs, xswndabs, xsxion, xszagauss, xszbabs, xszbbody, xszbremss, xszdust, xszedge, xszgauss, xszhighect, xszigm, xszpcfabs, xszphabs, xszpowerlw, xszredden, xszsmdust, xsztbabs, xszvarabs, xszvfeabs, xszvphabs, xszwabs, xszwndabs, xszxipcf

Last modified: December 2015
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