These models are based on Paolo Coppi's hybrid thermal/nonthermal hot plasma emission model for Xray binaries. The underlying physics and a detailed description of the code are included in the draft paper
http://www.astro.yale.edu/coppi/eqpair/eqpap4.ps.
Do not use these models without reading and understanding this paper. Simplified models eqtherm and compth are provided for cases where nonthermal processes are not important and photonphoton pair production can be ignored. These should only be used if l_{bb} <~ 10.
The temperature of the thermal component of the electron distribution and the total electron optical depth (for both ionization electrons and electronpositron pairs) are written out if the chatter level is set to 15. This information is important for checking selfconsistency.
In versions 1.10 and above the Compton reflection is done by a call to the ireflct model code and the relativistic blurring by a call to rdblur. This does introduce some changes in the spectrum from earlier versions. For the case of a neutral reflector (i.e. the ionization parameter is zero) more accurate opacities are calculated. For the case of an ionized reflector the old version assumed that for the purposes of calculating opacities the input spectrum was a powerlaw (with index based on the 210 keV spectrum). The new version uses the actual input spectrum, which is usually not a power law, giving different opacities for a given ionization parameter and disk temperature. The Greens' function integration required for the Compton reflection calculation is performed to an accuracy ofÂ 0.01 (i.e. 1%). This can be changed using e.g. xset EQPAIR_PRECISION 0.05.
The parameters for all three models are:
par1 
l_{h}/l_{s}, ratio of the hard to soft compactnesses 
par2 
l_{bb}, the soft photon compactness 
par3 
kT_{bb}, if > 0 then temperature of a blackbody; if < 0 then abs(kT_{bb}) is the T_{max} parameter for the diskpn model 
par4 
l_{nt}/l_{h}, fraction of power supplied to energetic particles which goes into accelerating nonthermal particles 
par5 
t_{p}, the Thomson scattering depth 
par6 
radius, the size of the scattering region (cm) 
par7 
g_{min}, minimum Lorentz factor of the pairs 
par8 
g_{max}, maximum Lorentz factor of the pairs 
par9 
G_{inj}, if < 0 then nonthermal spectrum is assumed monoenergetic at g_{max}; if > 0 then a powerlaw from g_{min} to g_{max} 
par10 
pairinj, if = 0 then accelerated particles are electrons from thermal pool; if = 1 then accelerated particles are electrons and positrons 
par11 
cosIncl, inclination of reflecting material wrt lineofsight 
par12 
Refl, fraction of scattering region's emission intercepted by reflecting material 
par13 
Fe_abund, relative abundance of iron 
par14 
Ab>He, relative abundance of other metals 
par15 
T_{disk}, temperature of reflecting disk 
par16 
x, ionization parameter of reflector 
par17 
b, powerlaw index with radius of disk reflection emissivity 
par18 
R_{in}, inner radius of reflecting material (GM/c^{2}) 
par19 
R_{out}, outer radius of reflecting material (GM/c^{2}) 
par20 
Redshift, z 
norm 
