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arXiv · 2103.10961

Dynamical Modeling of the CIV Broad Line Region of the $z=2.805$ Multiply Imaged Quasar SDSS J2222+2745

Peter R. Williams·Tommaso Treu·Håkon Dahle·Stefano Valenti·Louis Abramson·Aaron J. Barth·Brendon J. Brewer·Karianne Dyrland·Michael Gladders·Keith Horne·Keren Sharon
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Abstract

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 observer's 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 $τ_{\rm median} = 36.4^{+1.8}_{-1.8}$ 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 $\log_{10}(f_{{\rm mean},σ}) = 0.20^{+0.09}_{-0.07}$.

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Peter R. Williams, Tommaso Treu, Håkon Dahle, Stefano Valenti, Louis Abramson, Aaron J. Barth, Brendon J. Brewer, Karianne Dyrland, Michael Gladders, Keith Horne, Keren Sharon. 2021-03-19. Dynamical Modeling of the CIV Broad Line Region of the $z=2.805$ Multiply Imaged Quasar SDSS J2222+2745. https://doi.org/10.3847/2041-8213%2Fac081b

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