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Title: Tidal Disruption Event Demographics with the Zwicky Transient Facility: Volumetric Rates, Luminosity Function, and Implications for the Local Black Hole Mass Function

We conduct a systematic tidal disruption event (TDE) demographics analysis using the largest sample of optically selected TDEs. A flux-limited, spectroscopically complete sample of 33 TDEs is constructed using the Zwicky Transient Facility over 3 yr (from 2018 October to 2021 September). We infer the black hole (BH) mass (MBH) with host galaxy scaling relations, showing that the sampleMBHranges from 105.1Mto 108.2M. We developed a survey efficiency corrected maximum volume method to infer the rates. The rest-frameg-band luminosity function can be well described by a broken power law ofϕ(Lg)Lg/Lbk0.3+Lg/Lbk2.61, withLbk= 1043.1erg s−1. In the BH mass regime of 105.3≲ (MBH/M) ≲ 107.3, the TDE mass function followsϕ(MBH)MBH0.25, which favors a flat local BH mass function (dnBH/dlogMBHconstant). We confirm the significant rate suppression at the high-mass end (MBH≳ 107.5M), which is consistent with theoretical predictions considering direct capture of hydrogen-burning stars by the event horizon. At a host galaxy mass ofMgal∼ 1010M, the average optical TDE rate is ≈3.2 × 10−5galaxy−1yr−1. We constrain the optical TDE rate to be [3.7, 7.4, and 1.6] × 10−5galaxy−1yr−1in galaxies with red, green, and blue colors.

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Author(s) / Creator(s):
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Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal Letters
Page Range / eLocation ID:
Article No. L6
Medium: X
Sponsoring Org:
National Science Foundation
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