Published September 20, 2023 | Published
Journal Article Open

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

  • 1. ROR icon California Institute of Technology
  • 2. ROR icon University of California, Berkeley
  • 3. ROR icon Space Telescope Science Institute
  • 4. ROR icon Johns Hopkins University
  • 5. ROR icon Leiden University
  • 6. ROR icon Stockholm University
  • 7. ROR icon University of Maryland, College Park
  • 8. ROR icon University of Birmingham
  • 9. ROR icon Queen's University Belfast
  • 10. ROR icon Liverpool John Moores University
  • 11. NASA Goddard Space Flight Center
  • 12. ROR icon Harvard-Smithsonian Center for Astrophysics
  • 13. ROR icon Harvard University
  • 14. ROR icon Princeton University
  • 15. ROR icon University of Washington
  • 16. ROR icon Infrared Processing and Analysis Center

Abstract

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 sample MBH ranges from 105.1M⊙ to 108.2M⊙. We developed a survey efficiency corrected maximum volume method to infer the rates. The rest-frame g-band luminosity function can be well described by a broken power law of Ï•(Lg)∝[(Lg/Lbk)0.3+(Lg/Lbk)2.6]−1, with Lbk = 1043.1 erg s−1. In the BH mass regime of 105.3 â‰² (MBH/M⊙) ≲ 107.3, the TDE mass function follows Ï•(MBH)∝MBH−0.25, which favors a flat local BH mass function (dnBH/dlogMBH≈constant). We confirm the significant rate suppression at the high-mass end (MBH â‰³ 107.5M⊙), which is consistent with theoretical predictions considering direct capture of hydrogen-burning stars by the event horizon. At a host galaxy mass of Mgal ∼ 1010M⊙, the average optical TDE rate is ≈3.2 × 10−5 galaxy−1 yr−1. We constrain the optical TDE rate to be [3.7, 7.4, and 1.6] × 10−5 galaxy−1 yr−1 in galaxies with red, green, and blue colors.

Copyright and License

© 2023. The Author(s). Published by the American Astronomical Society.

Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Acknowledgement

We thank Jenny Greene for insightful discussions, and Ryan Chornock for providing the spectrum of PS1-11af. We thank Morgan MacLeod, Nick Stone, and Brian Metzger for constructive comments.

Y.Y. and S.R.K. acknowledge support from Heising-Simons Foundation. E.K.H. acknowledges support from NASA under award No. 80GSFC21M0002. M.N. is supported by the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation program (grant agreement No. 948381) and by funding from the UK Space Agency. This research benefited from interactions at workshops funded by the Gordon and Betty Moore Foundation through grant GBMF5076. This research was made possible in part through the support of grants from the Gordon and Betty Moore Foundation and the John Templeton Foundation. The opinions expressed in this publication are those of the author(s) and do not necessarily reflect the views of the Moore or Templeton Foundations.

This work is based on observations obtained with the Samuel Oschin Telescope 48 inch and the 60 inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under grants No. AST-1440341 and AST-2034437 and a collaboration including current partners Caltech, IPAC, the Weizmann Institute of Science, the Oskar Klein Center at Stockholm University, the University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories, IN2P3, University of Warwick, Ruhr University Bochum, Northwestern University and former partners the University of Washington, Los Alamos National Laboratories, and Lawrence Berkeley National Laboratories. Operations are conducted by Caltech Optical Observatories, IPAC, and University of Washington.

The ZTF forced-photometry service was funded under the Heising-Simons Foundation grant No. 12540303 (PI: Graham). SED Machine is based upon work supported by the National Science Foundation under grant No. 1106171.

This work has made use of data from the Asteroid Terrestrial-impact Last Alert System (ATLAS) project. The ATLAS project is primarily funded to search for near-Earth asteroids through NASA grants NN12AR55G, 80NSSC18K0284, and 80NSSC18K1575; byproducts of the near-earth object search include images and catalogs from the survey area. This work was partially funded by Kepler/K2 grant J1944/80NSSC19K0112 and Hubble Space Telescope GO-15889, and STFC grants ST/T000198/1 and ST/S006109/1. The ATLAS science products have been made possible through the contributions of the University of Hawaii Institute for Astronomy, the Queens University Belfast, the Space Telescope Science Institute, the South African Astronomical Observatory, and The Millennium Institute of Astrophysics (MAS), Chile.

Files

Yao_2023_ApJL_955_L6.pdf
Files (14.7 MB)
Name Size Download all
md5:3422fe36a1aa8708a4601c190c33df66
14.7 MB Preview Download

Additional details

Created:
April 22, 2025
Modified:
April 22, 2025