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Last modified: December 2008

URL: http://cxc.harvard.edu/sherpa4.1/lorentz2d.sl.html
AHELP for Sherpa 4.1

lorentz2d

Context: sl.sherpa

Synopsis

2-D unnormalized Lorentzian function.

Description

An unnormalized 2-D Lorentz model:

f(x,y) = f(r) = A (F/2)^2/[(F/2)^2 +r^2]

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) .

lorentz2d Parameters

Number Name Description
1 fwhm full-width at half-maximum F
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)

Bugs

See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.

See Also

sl.sherpa
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, lorentz1d, models, normbeta1d, normgauss1d, poisson, polynom1d, polynom2d, powlaw1d, 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, xsdiskline, xsdiskm, xsdisko, xsdiskpbb, xsdiskpn, xsdust, xsedge, xsequil, xsexpabs, xsexpdec, xsexpfac, xsezdiskbb, 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, 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
Last modified: December 2008



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