phabs, vphabs, zphabs, zvphabs: photoelectric absorption
A photoelectric absorption using cross-sections set by the xsect command. The relative abundances are set by the abund command.
![M(E) = exp[-n_H*sigma(E)]](XSmodelPhabs_files/image001.gif){kind=small}
where s(E) is the photo-electric cross-section (NOT including Thomson scattering). Note that the default He cross-section changed in v11. The old version can be recovered using the command
xsect obcm
|
par1= nH |
equivalent hydrogen column (in units of 1022 atoms cm–2) |
The redshifted variant, zphabs, uses the formula
![M(E) = exp[-n_H*sigma(E[1+z])]](XSmodelPhabs_files/image002.gif){kind=small}
and has parameters
|
par1= nH |
equivalent hydrogen column (in units of 1022 atoms cm–2) |
|
par2= z |
Redshift |
The variants vphabs, zvphabs allow the user to set fixed abundance parameters with respect to the solar composition, as defined by the abund command. For vphabs (rest-frame) the parameters are
|
par1= nH |
equivalent hydrogen column (in units of 1022 atoms cm–2) |
|
par2–par18 |
abundances for He, C, N, O, Ne, Na, Mg, Al, Si, S, Cl, Ar, Ca, Cr, Fe, Co, Ni wrt to Solar |
While the corresponding redshifted variant zvphabs has parameters
|
par1= nH |
equivalent hydrogen column (in units of 1022 atoms cm–2) |
|
par2-par18 |
abundances for He, C, N, O, Ne, Na, Mg, Al, Si, S, Cl, Ar, Ca, Cr, Fe, Co, Ni wrt to Solar (defined by the abund command) |
|
par19= z |
redshift |