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Last modified: September 2014

AHELP for CIAO 4.9 Sherpa v1


Context: models


calculate flux. XSpec convolution model *Experimental*.


A convolution model to calculate the flux of other model components.

The Sherpa commands calc_energy_flux, calc_photon_flux, and sample_flux, as well as the Calculating Model Flux and Flux Uncertainty thread can also be used.

xscflux Parameters

Number Name Description
1 Emin Minimum energy over which flux is calculated (keV)
2 Emax Maximum energy over which flux is calculated (keV)
3 lg10Flux log (base 10) flux in erg/cm^2/s

Loading the X-Spec convolution models

Please see ahelp xsconvolve for information on how to load the model.


  • This is an experimental release of the convolution models; please take care when using this model.
  • When cflux is used with multiple additive models, the normalization of one of the additive models must be fixed to a non-zero value.
  • The energy range defined by the Emin and Emax parameters must lie inside the energy range of the response matrix.
  • If the model to which cflux is applied integrates to zero then a divide-by-zero error will occur and the fit will likely fail due to the presence of NaN values.

XSpec version

This information is taken from the XSpec User's Guide. Version 12.8.0k of the XSpec models is supplied with CIAO 4.6.

Example 1

sherpa> from sherpa_contrib.xspec.xsconvole import load_xscflux
sherpa> load_xscflux("cflux")
sherpa> set_source(cflux(gal * (pl + gs)))

Flux of the absorbed model

If the power-law or gaussian normalization is fixed to a non-zero value then the above will calculate the flux and error on the entire model (absorbed).

Example 2

sherpa> set_source(gal * cflux(pl + gs)))

Flux of the un-absorbed model

If the power-law or gaussian normalization is fixed to a non-zero value then this calculates the unabsorbed flux and error.

Example 3

sherpa> set_source(gal * (pl + cflux(gs)))

Flux of a component

If the gaussian normalization is fixed to a non-zero value then this calculates the unabsorbed flux and error of the gaussian component.

About Contributed Software

This script is not an official part of the CIAO release but is made available as "contributed" software via the CIAO scripts page. Please see this page for installation instructions - such as how to ensure that the parameter file is available.


For a list of known bugs and issues with the XSPEC models, please visit the XSPEC bugs page.

See Also

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, load_xsgsmooth, load_xsireflect, load_xskdblur, load_xskdblur2, load_xskerrconv, load_xslsmooth, load_xspartcov, load_xsrdblur, load_xsreflect, load_xssimpl, load_xszashift, load_xszmshift, log, log10, logabsorption, logemission, logparabola, lorentz1d, lorentz2d, models, normbeta1d, normgauss1d, normgauss2d, opticalgaussian, poisson, polynom1d, polynom2d, polynomial, powerlaw, powlaw1d, recombination, scale1d, scale2d, schechter, seaton, sersic2d, shell2d, sigmagauss2d, sin, sm, smc, sqrt, stephi1d, steplo1d, tablemodel, tan, xgal, xs, xsabsori, xsacisabs, xsagauss, xsapec, xsbapec, xsbbody, xsbbodyrad, xsbexrav, xsbexriv, xsbkn2pow, xsbknpower, xsbmc, xsbremss, xsbvapec, xsbvvapec, xsc6mekl, xsc6pmekl, xsc6pvmkl, xsc6vmekl, xscabs, xscemekl, xscevmkl, xscflow, xscompbb, xscompls, xscompmag, xscompps, xscompst, xscomptb, xscompth, xscomptt, xsconstant, xsconvolve, 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, xsheilin, xshighecut, xshrefl, xskerrbb, xskerrd, xskerrdisk, xslaor, xslaor2, xslogpar, xslorentz, xslyman, xsmeka, xsmekal, xsmkcflow, xsnei, xsnotch, xsnpshock, xsnsa, xsnsagrav, xsnsatmos, xsnsmax, xsnsmaxg, xsnsx, xsnteea, xsnthcomp, xsoptxagn, xsoptxagnf, xspcfabs, xspegpwrlw, xspexmon, xspexrav, xspexriv, xsphabs, xsplabs, xsplcabs, xsposm, xspowerlaw, xspshock, xspwab, xsraymond, xsredden, xsredge, xsrefsch, xsrnei, 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, xsvrnei, xsvsedov, xsvvapec, xsvvgnei, xsvvnei, xsvvnpshock, xsvvpshock, xsvvrnei, xsvvsedov, xswabs, xswndabs, xsxion, xszagauss, xszbabs, xszbbody, xszbremss, xszdust, xszedge, xszgauss, xszhighect, xszigm, xszpcfabs, xszphabs, xszpowerlw, xszredden, xszsmdust, xsztbabs, xszvarabs, xszvfeabs, xszvphabs, xszwabs, xszwndabs, xszxipcf

Last modified: September 2014
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