In the merger-driven galaxy evolution scenario, dust-obscured quasars are considered to be an intermediate population between merger-driven star-forming galaxies and unobscured quasars; however, this scenario is still controversial. To verify this, it is necessary to investigate whether dust-obscured quasars have higher Eddington ratio (λEdd) values than those of unobscured quasars, as expected in the merger-driven galaxy evolution scenario. In this study, we derive black hole (BH) masses of 10 dust-obscured quasars at z ∼ 2, during the peak period of star-formation and BH growth in the Universe, using a newly derived mid-infrared (MIR) continuum luminosity (LMIR)-based estimator that is highly resistant to dust extinction. Then, we compare the λEdd values of these dust-obscured quasars to those of unobscured type-1 quasars at similar redshifts. We find that the measured log (λEdd) values of the dust-obscured quasars, −0.06 ± 0.10, are significantly higher than those of the unobscured quasars, −0.86 ± 0.01. This result remains consistent across the redshift range from 1.5 to 2.5. Our results show that the dust-obscured quasars are at their maximal growth, consistent with the expectation from the merger-driven galaxy evolution scenario at the epoch quasar activities were most prominent in the cosmic history.

1. Introduction
2. Sample
3. SED Fitting
4. Bolometric Luminosities and Black HoleMasses
    4.1. Bolometric Luminosities
    4.2. BH Masses
5. Eddington Ratios
6. Dicussion
    6.1. A Comparison of Bolometric Luminosities of Dust-Obscured Quasars Using Different MeasurementMethods
    6.2. Investigations on Host Galaxies of Dust-ObscuredQuasars Using HSC-SSP Data: Opportunities andProspects
7. Conclusion
Acknowledgments
References

• Dohyeong Kim(Department of Earth Sciences, Pusan National University, Busan 46241, Republic of Korea, Institute for Future Earth (IFE), Pusan National University, Busan 46241, Republic of Korea) Corresponding author
• Myungshin Im(Astronomy Program, Dept. of Physics & Astronomy, Seoul National University, Seoul 08826, Republic of Korea, SNU Astronomy Research Center (SNU ARC), Astronomy Program, Dept. of Physics & Astronomy, Seoul National University, Seoul 08826, Republic of Korea) Corresponding author
• Gu Lim(Department of Earth Sciences, Pusan National University, Busan 46241, Republic of Korea, Institute for Future Earth (IFE), Pusan National University, Busan 46241, Republic of Korea)
• Yongjung Kim(Korea Astronomy and Space Science Institute, Daejeon 34055, Republic of Korea)