lorentz: lorentz line profile

A Lorentzian line profile.

A(E) = K (\sigma/(2\pi))/[(E-E_L)^2 + (\sigma/2)^2]


par1 $E_L$, line energy in keV
par2 $\sigma$, FWHM line width in keV
norm $K$, photons/cm$^2$/s in the line

The line is truncated at the point that the integrated flux under the line is within a critical value of the total flux. This critical value can be changed using xset LINECRITLEVEL. The default critical value is $1.0\times10^{-6}$.