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Last modified: December 2008

URL: http://cxc.harvard.edu/sherpa4.1/devaucouleurs2d.sl.html
AHELP for Sherpa 4.1

devaucouleurs2d

Context: sl.sherpa

Synopsis

DeVaucouleurs profile.

Description

A 2-D de Vaucouleurs model:

f(x,y) = f(r) = A exp[-7.67 z^0.25 - 1 ]

where

z = sqrt[(x_maj/r_maj)^2+(x_min/r_min)^2]
r_maj = r_0
r_min = (1-epsilon)r_0
x_maj = (x-x_o)cos(theta) + (y-y_o)sin(theta)
x_min = -(x-x_o)sin(theta) + (y-y_o)cos(theta)

devaucouleurs2d Parmeters

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)

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, edge, erf, erfc, exp, exp10, gauss1d, gauss2d, hubblereynolds, jdpileup, linebroad, list_model_components, list_models, log, log10, lorentz1d, lorentz2d, 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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