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تسجيل مستخدم جديدDynamical Modeling of the CIV Broad Line Region of the $z=2.805$ Multiply Imaged Quasar SDSS J2222+2745
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We present CIV BLR modeling results for the multiply imaged $z=2.805$ quasar SDSS J2222+2745. Using data covering a 5.3 year baseline after accounting for gravitational time delays, we find models that can reproduce the observed emission-line spectra and integrated CIV fluctuations. The models suggest a thick disk BLR that is inclined by $sim$40 degrees to the observers line of sight and with a emissivity weighted median radius of $r_{rm median} = 33.0^{+2.4}_{-2.1}$ light days. The kinematics are dominated by near-circular Keplerian motion with the remainder inflowing. The rest-frame lag one would measure from the models is $tau_{rm median} = 36.4^{+1.8}_{-1.8}$ days, which is consistent with measurements based on cross-correlation. We show a possible geometry and transfer function based on the model fits and find that the model-produced velocity-resolved lags are consistent with those from cross-correlation. We measure a black hole mass of $log_{10}(M_{rm BH}/M_odot) = 8.31^{+0.07}_{-0.06}$, which requires a scale factor of $log_{10}(f_{{rm mean},sigma}) = 0.20^{+0.09}_{-0.07}$.
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