Name: Vivek Kumar Jha
Affiliation: ARIES Nainital
Conference ID : ASI2022_88
Title : Accretion disk sizes for quasars from the ZTF survey
Authors : Vivek Kumar Jha, Ravi Joshi, Hum Chand, Xue-Bing Wu, Luis C Ho, Shantanu Rastogi, Quinchun Ma
Abstract Type: Poster
Abstract Category : Extragalactic Astronomy
Abstract : An estimate of the size of accretion disks in AGN can be done by making use of continuum reverberation mapping. Recent results have shown that even though the disk sizes inferred from the wavelength-dependent interband reverberation lags follow the standard Shakura Sunyaev (SS) disk model, the magnitude of the interband lags is larger by a factor of 3-4 times larger than the expectation from a standard SS disk. Due to the limitations of high cadence multi-wavelength data, the measurement of disk sizes through this method is limited to a few sources. Using high cadence g,r and i band optical light curves from the Zwicky Transient Facility (ZTF) survey, we present the accretion disk sizes for a sample of 19 quasars with well-established Supermassive Black Hole (SMBH) masses. We find out that the measured inter-band reverberation lags and the accretion disk sizes are larger by an average of 3.9 times than the predictions of the SS disk model. We find a weak correlation between the accretion disk sizes and the SMBH mass. These results will be discussed in the context of recently obtained similar results and challenges in modeling the accretion disk in AGNs.