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wabs, zwabs: photoelectric absorption, Wisconsin cross-sections

A photo-electric absorption using Wisconsin (Morrison and McCammon; ApJ 270, 119) cross-sections.


\begin{displaymath}
M(E)=\exp[-\eta_H\sigma(E)]
\end{displaymath}

where $\sigma(E)$ is the photo-electric cross-section (NOT including Thomson scattering). Note that this model uses the Anders & Ebihara relative abundances (1982, Geochimica et Cosmochimica Acta 46, 2363) regardless of the abund command.

par1=$\eta_H$ equivalent hydrogen column (in units of $10^{22}$ atoms cm$^{-2}$)

The zwabs variant allows the user to specify a (fixed) redshift parameter, and uses the corresponding formula


\begin{displaymath}
M(E)=\exp[-\eta_H\sigma(E[1+z])]
\end{displaymath}

par1=$\eta_H$ equivalent hydrogen column (in units of $10^{22}$ atoms cm$^{-2}$)
par2=z redshift