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Last modified: December 2013

URL: http://cxc.harvard.edu/sherpa/ahelp/models.html
AHELP for CIAO 4.6 Sherpa v1

models

Context: models

Synopsis

Summary of Available Models

Description

The following is the list of models available within Sherpa.

Summary of Models

Name Description
atten Attenuation by ISM
bbody Blackbody as a function of energy
bbodyfreq Blackbody as a function of frequency
beta1d 1-D surface brightness beta-model
beta2d 2-D Lorentzian with varying power law
box1d 1-D box function
box2d 2-D box function
bpl1d Broken power law function
const1d 1-D constant amplitude model
const2d 2-D constant amplitude model
cos Cosine function
delta1d 1-D delta function
delta2d 2-D delta function
dered Dereddening function
devaucouleurs2d DeVaucouleurs profile
disk2d Uniform 2-D Disk model
edge Photoabsorption edge model
erf 1-D error function
erfc 1-D complementary error function
exp Exponential function
exp10 Exponential function, base 10
gauss1d 1-D unnormalized Gaussian function
gauss2d 2-D unnormalized Gaussian function
hubblereynolds Hubble-Reynolds profile
jdpileup John Davis (MIT) pileup model
linebroad Line broadening profile
log Natural logarithm function
logparabola Log-parabolic function
log10 Logarithm function, base 10
lorentz1d 1-D unnormalized Lorentzian function
lorentz2d 2-D unnormalized Lorentzian function
normbeta1d 1-D normalized beta function
normgauss1d 1-D normalized Gaussian function
poisson Poisson function
polynom1d 1-D polynomial function
polynom2d 2-D polynomial function
powlaw1d 1-D power law
scale1d const1d with the integrate flag turned off by default
scale2d const2d with the integrate flag turned off by default
schechter Schechter function
shell2d Homogeneous spherical shell, projected along the z-direction
sin Sine function
sqrt Square root function
stephi1d 1-D step function
steplo1d 1-D step function
tablemodel Table model class
tan Tangent function
XS<xspecname> the XSpec model functions

See "ahelp xs" for a list of XSPEC models available within Sherpa.

The integration of models in Sherpa is controlled by an integration flag in each model structure. Refer to "ahelp integrate" for information on integrating model components.

Changes in CIAO 4.6

New models

The disk2d and shell2d models are new, and were provided by Christoph Deil.

Fixed models

Errors in the absorptionvoigt and seaton models have been fixed.

Change to the theta parameter range

The minimum value for the theta parameter has been changed from 0 to -2PI.

Bugs

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

See Also

models
absorptionedge, absorptiongaussian, absorptionlorentz, absorptionvoigt, accretiondisk, atten, bbody, bbodyfreq, beta1d, beta2d, blackbody, box1d, box2d, bpl1d, bremsstrahlung, brokenpowerlaw, ccm, const1d, const2d, cos, delta1d, delta2d, dered, devaucouleurs2d, disk2d, edge, emissiongaussian, emissionlorentz, emissionvoigt, erf, erfc, exp, exp10, fm, gauss1d, gauss2d, hubblereynolds, jdpileup, linebroad, list_model_components, list_models, lmc, log, log10, logabsorption, logemission, logparabola, lorentz1d, lorentz2d, normbeta1d, normgauss1d, normgauss2d, opticalgaussian, poisson, polynom1d, polynom2d, polynomial, powerlaw, powlaw1d, recombination, scale1d, scale2d, schechter, seaton, sersic2d, shell2d, sin, sm, smc, sqrt, stephi1d, steplo1d, tablemodel, tan, xgal, xs, xsabsori, xsacisabs, xsapec, xsbapec, xsbbody, xsbbodyrad, xsbexrav, xsbexriv, xsbkn2pow, xsbknpower, xsbmc, xsbremss, xsbvapec, xsbvvapec, xsc6mekl, xsc6pmekl, xsc6pvmkl, xsc6vmekl, xscabs, xscemekl, xscevmkl, xscflow, xscompbb, xscompls, xscompps, xscompst, xscompth, xscomptt, xsconstant, xscplinear, xscutoffpl, xscyclabs, xsdisk, xsdiskbb, xsdiskir, xsdiskline, xsdiskm, xsdisko, xsdiskpbb, xsdiskpn, xsdust, xsedge, xseplogpar, xseqpair, xseqtherm, xsequil, xsexpabs, xsexpdec, xsexpfac, xsezdiskbb, xsgabs, xsgadem, xsgaussian, xsgnei, xsgrad, xsgrbm, xshighecut, xshrefl, xskerrbb, xskerrd, xskerrdisk, xslaor, xslaor2, xslogpar, xslorentz, xsmeka, xsmekal, xsmkcflow, xsnei, xsnotch, xsnpshock, xsnsa, xsnsagrav, xsnsatmos, xsnsmax, xsnteea, xsnthcomp, xsoptxagn, xsoptxagnf, xspcfabs, xspegpwrlw, xspexmon, xspexrav, xspexriv, xsphabs, xsplabs, xsplcabs, xsposm, xspowerlaw, xspshock, xspwab, xsraymond, xsredden, xsredge, xsrefsch, xssedov, xssirf, xssmedge, xsspexpcut, xsspline, xssrcut, xssresc, xssss_ice, xsstep, xsswind1, xstbabs, xstbgrain, xstbvarabs, xsuvred, xsvapec, xsvarabs, xsvbremss, xsvequil, xsvgadem, xsvgnei, xsvmcflow, xsvmeka, xsvmekal, xsvnei, xsvnpshock, xsvphabs, xsvpshock, xsvraymond, xsvsedov, xsvvapec, xswabs, xswndabs, xsxion, xszbbody, xszbremss, xszdust, xszedge, xszgauss, xszhighect, xszigm, xszpcfabs, xszphabs, xszpowerlw, xszredden, xszsmdust, xsztbabs, xszvarabs, xszvfeabs, xszvphabs, xszwabs, xszwndabs, xszxipcf

Last modified: December 2013
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