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URL: http://cxc.harvard.edu/sherpa/xsezdiskbb.html
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AHELP for CIAO 4.3 Sherpa v1

xsezdiskbb

Context: models

Synopsis

Multiple blackbody disk model with zero-torque inner boundary. XSpec model.

Description

A multi-temperature blackbody model for a thin, steady-state, Newtonian accretion disk, assuming zero torque at the inner boundary for the disk at radius R_in. The temperature of the disk as a function of radius is assumed to be

T(r) = T_* r^(-3/4) (1-r^(-1/2))^(1/4) ,

where r = R/R_in and

T_* = f(3 G M Mdot / 8 pi R_in^3 sigma)^(1/4) .

The maximum temperature in the disk is given by

T_max = 0.488 T_* .

This model is an alternative to xsdiskbb, which assumes a non-zero torque at the inner edge and a temperature profile

T(r) = T_* r^(-3/4) ,

and it should be used to fit spectra of disks when the zero-torque inner boundary condition is appropriate. For details see Zimmerman et al. (2004) astro-ph/0408209.

This is an additive model component.

xsezdiskbb Parameters

Number Name Description
1 t_max maximum temperature in the disk (keV)
2 norm (1/f^4) (R_in/D)^2 cos i, where R_in is the inner radius of the disk in km, D is the distance to the source in units of 10 kpc, i is the inclination, and f is the color to effective temperature ratio.

XSpec version

This information is taken from the XSpec User's Guide. Version 12.6.0l of the XSpec models is supplied with CIAO 4.3.

Bugs

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

See Also

models
atten, bbody, bbodyfreq, beta1d, beta2d, box1d, box2d, bpl1d, const1d, const2d, cos, delta1d, delta2d, dered, devaucouleurs2d, edge, erf, erfc, exp, exp10, gauss1d, gauss2d, hubblereynolds, jdpileup, linebroad, list_model_components, list_models, log, log10, logparabola, lorentz1d, lorentz2d, models, normbeta1d, normgauss1d, poisson, polynom1d, polynom2d, powlaw1d, scale1d, scale2d, schechter, sin, sqrt, stephi1d, steplo1d, tablemodel, tan, xs, xsabsori, xsacisabs, xsapec, xsbapec, xsbbody, xsbbodyrad, xsbexrav, xsbexriv, xsbkn2pow, xsbknpower, xsbmc, xsbremss, xsbvapec, xsc6mekl, xsc6pmekl, xsc6pvmkl, xsc6vmekl, xscabs, xscemekl, xscevmkl, xscflow, xscompbb, xscompls, xscompps, xscompst, xscomptt, xsconstant, xscutoffpl, xscyclabs, xsdisk, xsdiskbb, xsdiskir, xsdiskline, xsdiskm, xsdisko, xsdiskpbb, xsdiskpn, xsdust, xsedge, xsequil, xsexpabs, xsexpdec, xsexpfac, xsgabs, xsgaussian, xsgnei, xsgrad, xsgrbm, xshighecut, xshrefl, xskerrbb, xskerrd, xskerrdisk, xslaor, xslaor2, xslorentz, xsmeka, xsmekal, xsmkcflow, xsnei, xsnotch, xsnpshock, xsnsa, xsnsagrav, xsnsatmos, xsnsmax, xsnteea, xsnthcomp, xspcfabs, xspegpwrlw, xspexrav, xspexriv, xsphabs, xsplabs, xsplcabs, xsposm, xspowerlaw, xspshock, xspwab, xsraymond, xsredden, xsredge, xsrefsch, xssedov, xssmedge, xsspexpcut, xsspline, xssrcut, xssresc, xssss_ice, xsstep, xsswind1, xstbabs, xstbgrain, xstbvarabs, xsuvred, xsvapec, xsvarabs, xsvbremss, xsvequil, xsvgnei, xsvmcflow, xsvmeka, xsvmekal, xsvnei, xsvnpshock, xsvphabs, xsvpshock, xsvraymond, xsvsedov, xswabs, xswndabs, xsxion, xszbbody, xszbremss, xszdust, xszedge, xszgauss, xszhighect, xszpcfabs, xszphabs, xszpowerlw, xszredden, xszsmdust, xsztbabs, xszvarabs, xszvfeabs, xszvphabs, xszwabs, xszwndabs, xszxipcf

Last modified: December 2010
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