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rsapec, rsvapec, rsvvapec: APEC emission spectrum with resonance scattering

An emission spectrum from collisionally-ionized diffuse gas calculated from the AtomDB atomic database (http://atomdb.org/) modified by resonance scattering out of the beam following Chakraborty et al. (2023). This assumes an isothermal plasma and that there is no significant scattering into the beam. The free parameter for the resonance scattering is the column in units of 10$^{22}$ cm$^{-2}$. This model also includes a velocity broadening parameter and includes thermal broadening of all lines. The calculated line shape includes the different resonance scattering correction between the core and the wings. For large columns this can produce a double-peaked structure.

See the apec model for information about the additional options available.

For the rsapec 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)
par5 resonance scattering column ($10^{22}$ cm${^-2}$)
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 rsvapec 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)
par17 resonance scattering column ($10^{22}$ cm${^-2}$)
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 rsvvapec 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)
par34 resonance scattering column ($10^{22}$ cm${^-2}$)
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
Next: rsgauss: gaussian line profile Up: Additive Model Components Previous: rnei, vrnei, vvrnei, brnei,   Contents