xsvgadem

Context: models

Synopsis

Plasma emission, multi-temperature with gaussian distribution of emission measure. XSpec model.

A variant of the xsgadem model (see 'ahelp xsgadem' and model description below) which allows the user to define the abundances used in plasma-code models (for the xsgadem version, the abundance ratios are set by the set_xsabund command).

xsgadem/xsvgdem is a multi-temperature plasma emission model built on top of the apec or mekal codes (Sherpa 'xsapec' and 'xsmekal' models). The emission measure distribution is a gaussian with mean and sigma given by the 'Tmean' and 'Tsigma' model parameters. The 'switch' parameter determines whether the apec or mekal codes will be used. For the mekal code there are also the options to run the code for each temperature or interpolate from a pre-calculated table; the former is slower but more accurate. See the documentation on the apec model ('ahelp xsapec') for additional information on using different AtomDB versions or applying thermal or velocity broadening.

This is an additive model component.

xsvgadem Parameters

Number	Name	Description
1	Tmean	mean temperature for gaussian emission measure distribution
2	Tsigma	sigma temperature for gaussian emission measure distribution
3	nH	nH (cm^-3)
4-17	He, C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Fe, Ni	abundances relative to solar abundances (defined by the set_xsabund command)
18	Redshift	redshift z
19	switch	0: calculate using MEKAL model \| 1: interpolate using MEKAL model \| 2: interpolate using APEC model
20	norm	Normalization

XSpec version

This information is taken from the XSpec User's Guide. Version 12.7.1 of the XSpec models is supplied with CIAO 4.4.1.

Bugs

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

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, 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, models, normbeta1d, normgauss1d, normgauss2d, opticalgaussian, poisson, polynom1d, polynom2d, polynomial, powerlaw, powlaw1d, recombination, scale1d, scale2d, schechter, seaton, sersic2d, 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, 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