About

Dong Lai is Benson Jay and Mary Ellen Simon Professor and Professor of Astrophysics at Cornell University, currently on leave. He also holds the T.-D. Lee Chair Professor position at the Tsung-Dao Lee Institute in Shanghai. He received his Ph.D. in physics from Cornell in 1994 and was a postdoctoral fellow at Caltech before joining the faculty of the Astronomy Department at Cornell in 1997. His current research focuses on theoretical astrophysics, with particular emphasis on compact objects such as neutron stars, black holes, and white dwarfs, as well as exoplanets and astrophysical (particle and fluid) dynamics in general.

Research topics

• Astronomy
• Physics
• Astrophysics

Selected publications

• Hierarchical black hole mergers in multiple systems: constrain the formation of GW190412-, GW190814-, and GW190521-like events

  Monthly Notices of the Royal Astronomical Society · 2021 · 118 citations

  Senior authorCorresponding
  • Physics
  • Astrophysics
  • Astronomy

  ABSTRACT The merging black hole (BH) binaries GW190412, GW190814, and GW190521 from the third LIGO/VIRGO observing run exhibit some extraordinary properties, including highly asymmetric masses, significant spin, and component mass in the ‘mass gap’. These features can be explained if one or both components of the binary are the remnants of previous mergers. In this paper, we explore hierarchical mergers in multiple stellar systems, taking into account the natal kick and mass-loss due to the supernova explosion (SN) on each component, as well as the merger kick received by the merger remnant. The binaries that have survived the SNe and kicks generally have too wide orbital separations to merge by themselves, but can merge with the aid of an external companion that gives rise to Lidov–Kozai oscillations. The BH binaries that consist of second-generation BHs can also be assembled in dense star clusters through binary interactions. We characterize the parameter space of these BH binaries by merger fractions in an analytical approach. Combining the distributions of the survived binaries, we further constrain the parameters of the external companion, using the analytically formulated tertiary perturbation strength. We find that to produce the three LIGO/VIRGO O3 events, the external companions must be at least a few hundreds M⊙, and fall in the intermediate-mass BH and supermassive BH range. We suggest that GW190412, GW190814, and GW190521 could all be produced via hierarchical mergers in multiples, likely in a nuclear star cluster, with the final merger induced by a massive BH.

  DOI

Recent grants

• Tidal Dissipation and Evolution of Stars Around Massive Black Holes: An Eccentric Path to Tidal Disruption

  NSF · $555k · 2017–2021

• Matter and Radiation in Superstrong Magnetic Fields

  NSF · $357k · 2007–2010

• Tidal dissipation in compact white dwarf binaries and exoplanetary systems

  NSF · $468k · 2012–2016

• Dynamical Tides in White Dwarf Binaries: Theory and Applications

  NSF · $586k · 2021–2024

• Matter and Radiation in Superstrong Magnetic Fields

  NSF · $438k · 2010–2014

Frequent coauthors

• Xiang‐Dong Li

  48 shared

• Jiaru Li

  Los Alamos National Laboratory

  46 shared

• Bin Liu

  40 shared

• J. J. Zanazzi

  36 shared

• Ye-Fei Yuan

  32 shared

• Chen Wang

  31 shared

• Wynn C. G. Ho

  30 shared

• Ye‐Fei Yuan

  University of Science and Technology of China

  28 shared

Education

• Ph.D., Physics

  Cornell University

  1997

Awards & honors

• Sloan Fellowship
• Simons Fellowship
• graduate teaching and mentoring award from Cornell
• Dirk Brouwer Award from the American Astronomical Society (2…

Similar researchers at Cornell University

• Edward Bucklerh-182
• Robert Sternbergh-168
• John P. Mooreh-153
• Olivier Elementoh-150
• Andy Clarkh-142