lorentz: lorentz line profile

A Lorentzian line profile.

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

where:

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 $1.0\times10^{-6}$. Note also that the normalization is defined as the integral over energies greater than zero since negative energies are unphysical.

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Last modified: Friday, 23-Aug-2024 13:20:40 EDT