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Last modified: December 2006

URL: http://cxc.harvard.edu/ciao3.4/bbody.html
Hardcopy (PDF): A4 | Letter
AHELP for CIAO 3.4 bbody Context: sherpa

Synopsis

Blackbody as a function of energy. Integration ON.

Description

Blackbody emission calculated as a function of energy using the expression:

f(E) = A (E^2/exp[E/kT]-1) ,

where E is the photon energy, and kT is the blackbody temperature (expressed in the same units as the photon energy). The amplitude A is related to the ratio of source radius to distance:

A = (2pi/[c^2 h^3]) (R/d)^2 = 9.884 x 10^31 (R/d)^2 ,

with Planck's constant h specified in keV-s and the speed of light c specified in cm/s, and with R and d representing the radius of, and distance to, the source respectively. If E/kt < 10^-4, f(E) = AEkT, while if E/kT > 60, f(E) = 0.

BBODY Parameters

Number Name Description
1 space 0: energy | 1: wavelength
2 kT temperature kT (in energy units)
3 ampl amplitude A

See "ahelp integrate" for further information about source model integration.

Bugs

See the Sherpa bug pages online for an up-to-date listing of known bugs.

See Also

sherpa
atten, bbodyfreq, beta1d, beta2d, box1d, box2d, bpl1d, const1d, const2d, cos, delta1d, delta2d, dered, devaucouleurs, edge, erf, erfc, farf, farf2d, fpsf, fpsf1d, frmf, gauss1d, gauss2d, gridmodel, hubble, jdpileup, linebroad, lorentz1d, lorentz2d, models, nbeta, ngauss1d, poisson, polynom1d, polynom2d, powlaw1d, ptsrc1d, ptsrc2d, rsp, rsp2d, schechter, shexp, shexp10, shlog10, shloge, sin, sqrt, stephi1d, steplo1d, tan, tpsf, tpsf1d, usermodel, xs, xsabsori, xsacisabs, xsapec, xsbapec, xsbbody, xsbbodyrad, xsbexrav, xsbexriv, xsbknpower, xsbmc, xsbremss, xsbvapec, xsc6mekl, xsc6pmekl, xsc6pvmkl, xsc6vmekl, xscabs, xscemekl, xscevmkl, xscflow, xscompbb, xscompls, xscompst, xscomptt, xsconstant, xscutoffpl, xscyclabs, xsdisk, xsdiskbb, xsdiskline, xsdiskm, xsdisko, xsdiskpn, xsdust, xsedge, xsequil, xsexpabs, xsexpdec, xsexpfac, xsgabs, xsgaussian, xsgnei, xsgrad, xsgrbm, xshighecut, xshrefl, xslaor, xslorentz, xsmeka, xsmekal, xsmkcflow, xsnei, xsnotch, xsnpshock, xsnsa, xsnteea, xspcfabs, xspegpwrlw, xspexrav, xspexriv, xsphabs, xsplabs, xsplcabs, xsposm, xspowerlaw, xspshock, xspwab, xsraymond, xsredden, xsredge, xsrefsch, xssedov, xssmedge, xsspline, xssrcut, xssresc, xssssice, xsstep, xstbabs, xstbgrain, xstbvarabs, xsuvred, xsvapec, xsvarabs, xsvbremss, xsvequil, xsvgnei, xsvmcflow, xsvmeka, xsvmekal, xsvnei, xsvnpshock, xsvphabs, xsvpshock, xsvraymond, xsvsedov, xswabs, xswndabs, xsxion, xszbbody, xszbremss, xszedge, xszgauss, xszhighect, xszpcfabs, xszphabs, xszpowerlw, xsztbabs, xszvarabs, xszvfeabs, xszvphabs, xszwabs, xszwndabs
slang
usermodel
Hardcopy (PDF): A4 | Letter
Last modified: December 2006



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