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To find and download HEASARC data in the cloud, you can use astroquery.heasarc or download our new tool, hark.

The HEASARC and NuSTAR teams are greatly saddened by the sudden passing of Katja Pottschmidt. Most recently Katja was the lead scientist for the NuSTAR Guest Observer Facility (GOF), a role she had supported for many years. During her science career she worked on many other high energy astrophysics missions and played an integral role in advancing our knowledge of the universe. She was a wonderful colleague and friend and will be keenly missed by all who knew her.

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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$^{-3}$)

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