The Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center (GSFC) seeks a creative, innovative individual with strong teamwork and leadership skills to serve as Director of the High Energy Astrophysics Science Archive Research Center (HEASARC). This will be a permanent civil servant position. + Learn more.

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Next: wndabs, zwndabs: photo-electric absorption, Up: Multiplicative Model Components Previous: vgabs, zvgabs: gaussian absorption


wabs, zwabs: photoelectric absorption, Wisconsin cross-sections

A photo-electric absorption using Wisconsin (Morrison & McCammon 1983) cross-sections.

$\displaystyle M(E)=\exp[-\eta_H\sigma(E)] $

where $\sigma(E)$ is the photo-electric cross-section (NOT including Thomson scattering). Note that this model uses the Anders & Ebihara relative abundances (1982) 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

$\displaystyle M(E)=\exp[-\eta_H\sigma(E[1+z])] $

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

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

The Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center (GSFC) seeks a creative, innovative individual with strong teamwork and leadership skills to serve as Director of the High Energy Astrophysics Science Archive Research Center (HEASARC). This will be a permanent civil servant position. + Learn more.