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diskir: Irradiated inner and outer disk

The inner disk can be irradiated by the Compton tail. This can substantially change the inner disk temperature structure from that expected from an unilluminated disk in the limit where the ratio of luminosity in the tail to that in the disk, $L_c/L_d >> 1$. This is generally the case in the low/hard state of accreting black holes, and neglecting this effect leads to an underestimate of the inner disk radius (Gierlinski, Done & Page 2008a MNRAS, 388, 753).

The irradiated inner disk and Compton tail can illuminate the rest of the disk, and a fraction $f_{out}$ of the bolometric flux is thermalized to the local blackbody temperature at each radius. This reprocessed flux generally dominates the optical and UV bandpass of LMXBs (Gierlinski, Done & Page 2009 MNRAS, 392, 1106).

par1 kT_disk, innermost temperature of the UNILLUMINATED disk
par2 Gamma, asymptotic power-law photon index
par3 kT_e, electon temperature (high energy rollover)
par4 Lc/Ld, ratio of luminosity in the Compton tail to that of the UNILLUMINATED disk
par5 fin, fraction of luminosity in the Compton tail which is thermalized in the inner disk (generally fix at 0.1 as appropriate for an albedo of 0.3 and solid angle of 0.3)
par6 rirr, radius of the Compton illuminated disk in terms of the inner disk radius
par7 fout, fraction of bolometric flux which is thermalized in the outer disk
par8 logrout, log10 of the outer disk radius in terms of the inner disk radius K = normalization, as in diskbb


next up previous contents
Next: diskline: accretion disk line Up: Additive Model Components Previous: diskbb: accretion disk, multi-black