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raymond, vraymond: emission, hot diffuse gas, Raymond-Smith

An emission spectrum from hot, diffuse gas based on the model calculations of Raymond & Smith (1977) including line emissions from several elements. This model interpolates on a grid of spectra for different temperatures. The grid is logarithmically spaced with 80 temperatures ranging from 0.008 to 80 keV.

The vraymond variant allows independent parameters to set the abundances. Abundances are the number of nuclei per Hydrogen nucleus relative to the Solar abundances as set by the abund command.

For the raymond model the parameters are:

par1 plasma temperature, keV
par2 Metal abundances (He fixed at that defined by the abund command). The elements included are C, N, O, Ne, Mg, Si, S, Ar, Ca, Fe, Ni. Relative abundances are set by the abund command.
par3 Redshift, z
norm ${10^{-14}\over{4\pi[D_A(1+z)]^2}}\int n_en_HdV$, where $D_A$ is the angular diameter distance to the source (cm), $dV$ is the volume element (cm$^3$), and $n_e$ and $n_H$ are the electron and H densities (cm$^{-3}$), respectively

For the vraymond variant the parameters are as follows.

par1 plasma temperature, keV
par2–par13 Abundances for He, C, N, O, Ne, Mg, Si, S, Ar, Ca, Fe, Ni wrt Solar (defined by the abund command).
par14 redshift, z
norm ${10^{-14}\over{4\pi[D_A(1+z)]^2}}\int n_en_HdV$, where $D_A$ is the angular diameter distance to the source (cm), $dV$ is the volume element (cm$^3$), and $n_e$ and $n_H$ are the electron and H densities (cm$^{-3}$), respectively
next up previous contents Xspec Home Page
Next: redge: emission, recombination edge Up: Additive Model Components Previous: pshock, vpshock, vvpshock, bpshock,
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Last modified: Friday, 23-Aug-2024 13:20:40 EDT

HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.