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Calculates the absorption of X-rays by the ISM, allowing user to vary
all abundances, depletion factors, and grain properties.
XSpec model.
The Tuebingen-Boulder ISM absorption model. This model calculates the
cross-section for X-ray absorption by the ISM as the sum of the
cross-sections for X-ray absorption due to the gas-phase ISM, the
grain-phase ISM, and the molecules in the ISM. In the grain-phase ISM,
the effect of shielding by the grains is accounted for, but is
extremely small. In the molecular contribution to the ISM
cross-section, only molecular hydrogen is considered. In the gas-phase
ISM,
the cross-section is the sum of the photoionization cross-sections of
the different elements, weighted by abundance and taking into account
depletion onto grains. In addition to the updates to the
photoionization cross-sections, the gas-phase cross-section differs
from previous values as a result of updates to the ISM
abundances. Details of updates to the photoionization cross-sections
as well as to abundances can be found in Wilms, Allen and McCray
(2000, ApJ 542, 914). This model allows the user to vary the molecular
hydrogen column, the grain distribution parameters, and the abundances
and grain depletions.
xstbvarabs Parameters
| 1 | nH | equivalent
hydrogen column (in units of 10^22 atoms/cm^2) |
| 2-18 | (element) | columns
of He, C, N, O, Ne, Na, Mg, Al, Si, S, Cl, Ar, Ca, Cr, Fe, Co, Ni
(in units of 10^22 atoms/cm^2) |
| 19 | H2 | molecular
hydrogen column (in units of 10^22 atoms/cm^2) |
| 20 | rho | grain density
(in gm/cm^3) |
| 21 | amin | grain minimum
size (in microns) |
| 22 | amax | grain maximum
size (in microns) |
| 23 | PL | power law index
of grain sizes |
| 24-41 | (element)Dep |
grain depletion fractions of He, C, N, O, Ne, Na, Mg, Al, Si,
S, Cl, Ar, Ca, Cr, Fe, Co, Ni |
| 42 | Redshift | redshift,
z |
This information is taken from the XSpec User's Guide. Version 11.3.1 of the XSpec
models is supplied with CIAO 3.2.
For a list of known bugs and issues with the XSPEC models, please visit the XSPEC bugs page.
- 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,
xsc6pvmkl,
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,
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
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usermodel
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