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Last modified: December 2006

URL: http://cxc.harvard.edu/ciao3.4/beta2d.html
Hardcopy (PDF): A4 | Letter
AHELP for CIAO 3.4 beta2d Context: sherpa

Synopsis

2-D Lorentzian with varying power law. Integration OFF. The LORPOW2D model is equivalent.

Description

A 2-D Lorentz model with a varying power law, also known as a Beta model:

f(x,y) = f(r) = A/(1+[r/r_0]^2)^alpha ,

where

r(x,y) = sqrt[x_new^2(1-epsilon)^2 + y_new^2]/(1-epsilon) ,
x_new = (x-x_o)cos(theta) + (y-y_o)sin(theta) ,

and

y_new = (y-y_o)cos(theta) - (x-x_o)sin(theta) .

BETA2D Parameters

Number Name Description
1 r0 core radius r_0
2 xpos x mean position x_o
3 ypos y mean position y_o
4 ellip ellipticity epsilon
5 theta angle of ellipticity theta
6 ampl amplitude A at (x_o,y_o)
7 alpha power law index alpha

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, bbody, bbodyfreq, beta1d, 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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