Reconciling the Quasar Microlensing Disc Size Problem with a Wind Model of Active Galactic Nucleus

Journal Article · 28 November 2018 · Monthly Notices of the Royal Astronomical Society

DOI: https://doi.org/10.1093/mnras/sty3245 · OSTI ID:1492680

Li, Yaping  ^[1]; Yuan, Feng ^[2]; Dai, Xinyu ^[3]

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1. Chinese Academy of Sciences (CAS), Beijing (China). Key Lab. for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory; Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2. Chinese Academy of Sciences (CAS), Beijing (China). Key Lab. for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory; Chinese Academy of Sciences (CAS), Beijing (China). School of Astronomy and Space Sciences
3. Univ. of Oklahoma, Norman, OK (United States). Dept. of Physics and Astronomy

Many analyses have concluded that the accretion disc sizes measured from the microlensing variability of quasars are larger than the expectations from the standard thin disc theory by a factor of ~4. We propose a simple model by invoking a strong wind from the disc to flatten its radial temperature profile, which can then reconcile the size discrepancy problem. This wind model has been successfully applied to several microlensed quasars with a wind strength s ≲ 1.3 by only considering the inward decreasing of the mass accretion rate [where s is defined through $$∙\atop{M}$$(R)∝(R/R₀)^s]. After further incorporating the angular momentum transferred by the wind, our model can resolve the disc size problem with an even lower wind parameter. Finally, the corrected disc sizes under the wind model are correlated with black hole masses with a slope in agreement with our modified thin disc model.

• Research Organization: Los Alamos National Laboratory (LANL)
• Sponsoring Organization: National Key Research and Development Program of China; National Natural Science Foundation of China (NNSFC); USDOE
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 1492680
• Report Number(s): LA-UR-18-31527
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Journal Issue: 2 Vol. 483; ISSN 0035-8711
• Publisher: Royal Astronomical SocietyCopyright Statement
• Country of Publication: United States
• Language: English