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Last modified: December 2006

URL: http://cxc.harvard.edu/ciao3.4/xsc6pvmkl.html
Hardcopy (PDF): A4 | Letter
AHELP for CIAO 3.4 xsc6pvmkl Context: sherpa

Synopsis

Variable abundance version of c6pmekl. XSpec model.

Description

A multi-temperature, variable-abundance mekal model using the exponential of a sixth-order Chebyshev polynomial for the differential emission measure (e.g. Lemen et al. ApJ 341, 474, 1989). The abundances are relative to the Solar abundances set by the xspecabundan command. The switch parameter determines whether the mekal code will be run to calculate the model spectrum for each temperature, or whether the model spectrum will be interpolated from a pre-calculated table; the former is slower but more accurate. The reference for this model is Singh et al. (1996, ApJ, 456, 766).

xsc6mekl Parameters

Number Name Description
1 CPcoef1 Chebyshev polynomial coefficient 1
2 CPcoef2 Chebyshev polynomial coefficient 2
3 CPcoef3 Chebyshev polynomial coefficient 3
4 CPcoef4 Chebyshev polynomial coefficient 4
5 CPcoef5 Chebyshev polynomial coefficient 5
6 CPcoef6 Chebyshev polynomial coefficient 6
7 nH H density (cm^-3)
8-21 (element) Abundances for He, C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Fe, Ni with respect to Solar
22 redshift redshift, z
23 switch 0 = calculate, 1 = interpolate
24 norm 10^-14/(4 pi (D_A*(1+z))^2) Int n_e n_H dV, where D_A is the angular size distance to the source (cm), n_e is the electron density (cm^-3), and n_H is the hydrogen density (cm^-3)

This information is taken from the XSpec User's Guide. Version 11.3.1 of the XSpec models is supplied with CIAO 3.2.

Bugs

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

See Also

sherpa
atten, bbody, bbodyfreq, beta1d, beta2d, box1d, box2d, bpl1d, const1d, const2d, cos, delta1d, delta2d, dered, devaucouleurs, edge, erf, erfc, farf, farf2d, fpsf, fpsf1d, frmf, gauss1d, gauss2d, gridmodel, hubble, jdpileup, linebroad, lorentz1d, lorentz2d, models, nbeta, ngauss1d, poisson, polynom1d, polynom2d, powlaw1d, ptsrc1d, ptsrc2d, rsp, rsp2d, schechter, shexp, shexp10, shlog10, shloge, sin, sqrt, stephi1d, steplo1d, tan, tpsf, tpsf1d, usermodel, xs, xsabsori, xsacisabs, xsapec, xsbapec, xsbbody, xsbbodyrad, xsbexrav, xsbexriv, xsbknpower, xsbmc, xsbremss, xsbvapec, xsc6mekl, xsc6pmekl, xsc6vmekl, xscabs, xscemekl, xscevmkl, xscflow, xscompbb, xscompls, xscompst, xscomptt, xsconstant, xscutoffpl, xscyclabs, xsdisk, xsdiskbb, xsdiskline, xsdiskm, xsdisko, xsdiskpn, xsdust, xsedge, xsequil, xsexpabs, xsexpdec, xsexpfac, xsgabs, xsgaussian, xsgnei, xsgrad, xsgrbm, xshighecut, xshrefl, xslaor, xslorentz, xsmeka, xsmekal, xsmkcflow, xsnei, xsnotch, xsnpshock, xsnsa, xsnteea, xspcfabs, xspegpwrlw, xspexrav, xspexriv, xsphabs, xsplabs, xsplcabs, xsposm, xspowerlaw, xspshock, xspwab, xsraymond, xsredden, xsredge, xsrefsch, xssedov, xssmedge, xsspline, xssrcut, xssresc, xssssice, xsstep, xstbabs, xstbgrain, xstbvarabs, xsuvred, xsvapec, xsvarabs, xsvbremss, xsvequil, xsvgnei, xsvmcflow, xsvmeka, xsvmekal, xsvnei, xsvnpshock, xsvphabs, xsvpshock, xsvraymond, xsvsedov, xswabs, xswndabs, xsxion, xszbbody, xszbremss, xszedge, xszgauss, xszhighect, xszpcfabs, xszphabs, xszpowerlw, xsztbabs, xszvarabs, xszvfeabs, xszvphabs, xszwabs, xszwndabs
slang
usermodel
Hardcopy (PDF): A4 | Letter
Last modified: December 2006



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