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mekal, vmekal: emission, hot diffuse gas (Mewe-Gronenschild-Kaastra)

An emission spectrum from hot diffuse gas based on the model calculations of Mewe and Kaastra with Fe L calculations by Liedahl. The model includes line emissions from several elements. The switch parameter determines whether spectrum is calculated by running the mekal code, by interpolating on a pre-calculated mekal table, or using the AtomDB data. Relative abundances are set by the abund command for the mekal model. The vmekal variant allows the user to set the individual abundances for the model.

For the mekal model the parameters are:

par1 plasma temperature in keV
par2 H density (cm$^{-3}$
par3 Metal abundances (He fixed at that defined by the abund command). The elements included are C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Fe, Ni. Relative abundances are set by the abund command.
par4 Redshift, z
par5 Switch (0 = calculate, 1 = interpolate, 2 = interpolate using AtomDB data)
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 vmekal variant the parameters are as follows.

par1 plasma temperature in keV
par2 H density (cm$^{-3}$
par3–par16 Abundances for He, C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Fe, Ni wrt Solar (defined by the abund command).
par17 redshift, z
par18 Switch (0 = calculate, 1 = interpolate, 2 = interpolate using AtomDB data)
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

The references for the meka model are as follows :
Mewe, Gronenschild & van den Oord (1985)
Mewe, Lemen, & van den Oord (1986)
Kaastra, J.S. 1992, An X-Ray Spectral Code for Optically Thin Plasmas (Internal SRON-Leiden Report, updated version 2.0)
Liedahl, Osterheld & Goldstein (1995)

Similar credit may also be given for the adopted ionization balance:
Arnaud & Rothenflug (1985)
Arnaud & Raymond (1992)

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Next: mkcflow, vmcflow: cooling flow, Up: Additive Model Components Previous: meka, vmeka: emission, hot   Contents