vphabs

A photoelectric absorption with variable abundances using Balucinska-Church and McCammon (ApJ 400, 699) cross-sections. The relative abundances are set by the abund command. This model is identical to varabs except for the way that the parameters are defined.

where is the photo-electric cross-section (NOT including Thomson scattering) and

par1	   =  	equivalent hydrogen column (in units of  atoms/cm )

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)