Dynamical modeling of the C iv broad line region of the z=2.805 multiply imaged quasar SDSS J2222+2745
Abstract
We present the first ever models of a broad line region (BLR) at the peak of active galactic nucleus (AGN) activity using the multiply imaged z = 2.805 quasar SDSS J2222+2745. The modeled data consist of monthly spectra covering the broad C IV emission line over a 5.3 yr baseline. The models suggest a thick disk BLR that is inclined by degrees 40 degrees to the observer's line of sight and with an emissivity weighted median radius of = rmedian = 33.0(-2.1)(+2.44) light days. The kinematics are dominated by near-circular Keplerian motion with the remainder inflowing. The restframe lag one would measure from the models is taumedian = 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 log10(MBH/M⊙) = 8.31(-0.06)(+0.07), which requires a scale factor of log10 (fmean,σ) = 0.20(-0.07)(+0.09.). This is the most precise MBH measurement for any AGN at cosmological distances and it demonstrates that the precision required for BH-host coevolution studies is attainable.
Citation
Williams , P R , Treu , T , Dahle , H , Valenti , S , Abramson , L , Barth , A J , Brewer , B J , Dyrland , K , Gladders , M , Horne , K & Sharon , K 2021 , ' Dynamical modeling of the C iv broad line region of the z =2.805 multiply imaged quasar SDSS J2222+2745 ' , Astrophysical Journal Letters , vol. 915 , no. 1 . https://doi.org/10.3847/2041-8213/ac081b
Publication
Astrophysical Journal Letters
Status
Peer reviewed
ISSN
2041-8205Type
Journal article
Rights
Copyright © 2021 American Astronomical Society. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the author created accepted manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.3847/2041-8213/ac081b.
Description
P.W. and T.T. gratefully acknowledge support by the National Science Foundation through grant AST-1907208 "Collaborative Research: Establishing the foundations of black hole mass measurements of AGN across cosmic time" and by the Packard Foundation through a Packard Research Fellowship to T.T. Research at UC Irvine was supported by NSF grant AST-1907290. K.H. acknowledges support from STFC grant ST/R000824/1.Collections
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