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Last modified: December 2007

URL: http://cxc.harvard.edu/sherpabeta/bpl1d.py.html
AHELP for Sherpa 4.0 Beta bpl1d Context: py.sherpa

Synopsis

Broken power law function.

Description

A broken power-law model:

f(x) = A (x/x_ref)^(-gamma_1)

if x <= x_b, and

f(x) = A' (x/x_ref)^(-gamma_2)

otherwise, where

A' = A (x_b/x_ref)^(gamma_2-gamma_1)

bpl1d Parameters

Number Name Description
1 gamma1 first power law photon index gamma_1
2 gamma2 second power law photon index gamma_2
3 eb break-point x_b
4 ref normalization reference point x_ref
5 ampl amplitude A

Bugs

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

See Also

py.sherpa
atten, bbody, bbodyfreq, beta1d, beta2d, box1d, box2d, const1d, const2d, cos, delta1d, delta2d, dered, devaucouleurs2d, edge, erf, erfc, exp, exp10, gauss1d, gauss2d, hubblereynolds, jdpileup, linebroad, log, log10, lorentz1d, lorentz2d, models, normbeta1d, normgauss1d, poisson, polynom1d, polynom2d, powlaw1d, psf1d, psf2d, 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, xslaor, xslaor2, xslorentz, xsmeka, xsmekal, xsmkcflow, xsnei, xsnotch, xsnpshock, xsnsa, xsnsagrav, xsnsatmos, xsnteea, xspcfabs, xspegpwrlw, xspexrav, xspexriv, xsphabs, xsplabs, xsplcabs, xsposm, xspowerlaw, xspshock, xspwab, xsraymond, xsredden, xsredge, xsrefsch, xssedov, xssmedge, 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 2007



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