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bapec, bvapec, bvvapec: velocity broadened APEC thermal plasma model

A velocity- and thermally-broadened emission spectrum from collisionally-ionized diffuse gas calculated from the AtomDB atomic database. More information can be found at http://atomdb.org/ which should be consulted by anyone running this model. This default version number can be changed by modifiying the ATOMDB_VERSION string in your Xspec.init file.

See the documentation on the apec model for a list of the xset options which can be used to change the behaviour of the apec code.

For the bapec 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, Al, Si, S, Ar, Ca, Fe, Ni. Relative abundances are set by the abund command. The trace element abundances are from xset APEC_TRACE_ABUND, the default is 1.0.
par3 Redshift, z
par4 Gaussian sigma for velocity broadening (km/s)
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), $n_e$ and $n_H$ are the electron and H densities (cm$^{-3}$), respectively

For the bvapec variant the parameters are as follows.

par1 plasma temperature, keV
par2-par14 Abundances for He, C, N, O, Ne, Mg,Al, Si, S, Ar, Ca, Fe, Ni wrt Solar (defined by the abund command). The trace element abundances are from xset APEC_TRACE_ABUND, the default is 1.0.
par15 redshift, z
par16 Gaussian sigma for velocity broadening (km/s)
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), $n_e$ and $n_H$ are the electron and H densities (cm$^{-3}$), respectively

For the bvvapec variant the parameters are as follows.

par1 plasma temperature, keV
par2-par31 Abundances for H, He, Li, Be, B, C, N, O, F, Ne, Na, Mg, Al, Si, P, S, Cl, Ar, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn wrt Solar (defined by the abund command)
Par32 redshift, z
Par33 Gaussian sigma for velocity broadening (km/s)
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), $n_e$ and $n_H$ are the electron and H densities (cm$^{-3}$), respectively


next up previous contents
Next: bbody, zbbody: blackbody Up: Additive Model Components Previous: atable: tabulated additive model