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bbody, zbbody: blackbody

A blackbody spectrum.

$\displaystyle A(E) = {{K \times 8.0525 E^2 dE}\over{(kT)^4[\exp(E/kT)-1]}} $

where

par1= kT temperature keV
norm= K $L_{39}/D_{10}^2$, where $L_{39}$ is the source luminosity in units of $10^{39}$ erg/s and $D_{10}$ is the distance to the source in units of 10 kpc.

The zbbody variant allows an additional redshift parameter

$\displaystyle A(E) = {{K \times 8.0525 [E(1+z)]^2 dE}\over{(1+z)(kT)^4[\exp[E(1+z)/kT]-1]}} $

where

par1= kT temperature keV
z redshift
norm= K $L_{39}/[D_{10}(1+z)]^2$, where $L_{39}$ is the source luminosity in units of $10^{39}$ erg/s and $D_{10}$ is the distance to the source in units of 10 kpc.