next up previous contents
Next: xion: reflected spectrum of Up: Multiplicative Model Components Previous: wabs, zwabs: photoelectric absorption,


wndabs, zwndabs: photo-electric absorption, warm absorber

Photo-electric absorption from approximation to a warm absorber using Balucinska,-Church, and McCammon (ApJ 400, 699) cross-sections. Relative abundances are set by the abund command.


\begin{displaymath}
M(E) = \begin{array}{ll}
1 & E > E_w \\ [.2cm]
\exp[-\eta_H\sigma(E)] & E \leq E_w
\end{array}\end{displaymath}

where $\sigma(E)$ is the photo-electric cross-section (NOT including Thomson scattering) and

par1=$\eta_H$ equivalent hydrogen column (in units of $10^{22}$ atoms cm$^{-2}$)
par2=$E_w$ window energy (keV)

The zwndabs variant allows the user to specify a (fixed) redshift and uses the corresponding formula:


\begin{displaymath}
M(E) = \begin{array}{ll}
1 & E > E_w \\ [.2cm]
\exp[-\eta_H\sigma(E[1+z])] & E \leq E_w
\end{array}\end{displaymath}

with parameters:

par1=$\eta_H$ equivalent hydrogen column (in units of $10^{22}$ atoms cm$^{-2}$)
par2=$E_w$ window energy (keV)
par3=z redshift