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bremss, vbremss, zbremss: thermal bremsstrahlung

A thermal bremsstrahlung spectrum based on the Kellogg, Baldwin & Koch (1975, ApJ 199, 299) polynomial fits to the Karzas & Latter (1961, ApJS 6, 167) numerical values. A routine from Kurucz (private communication) is used at the low temperature end. The He abundance is assumed to be 8.5 % of H by number.

The zbremss variant includes a choice of redshift and vbremss allows the H to He abundance ratio to be varied.

For bremss:

par1 plasma temperature in keV
norm ${3.02\times10^{-15}\over{4\pi D^2}} \int n_e n_I dV$, where $D$ is the distance to the source (cm) and $n_e$, $n_I$ are the electron and ion densities (cm$^{-3}$)

For zbremss:

par1 plasma temperature in keV
par2 z, redshift
norm ${3.02\times10^{-15}\over{4\pi D^2}} \int n_e n_I dV$, where $D$ is the distance to the source (cm) and $n_e$, $n_I$ are the electron and ion densities (cm$^{-3}$)

For vbremss:

par1 plasma temperature in keV
par2 $n(\mbox{He})/n(\mbox{H})$ ((note that the Solar ratio is 0.085)
norm ${3.02\times10^{-15}\over{4\pi D^2}} \int n_e n_I dV$, where $D$ is the distance to the source (cm) and $n_e$, $n_I$ are the electron and ion densities (cm$^{-3}$)

next up previous contents
Next: btapec, bvtapec, bvvtapec: velocity Up: Additive Model Components Previous: bmc: Comptonization by relativistic   Contents