Tidal Disruptions of Stars by Black Hole Remnants in Dense Star Clusters

Kyle Kremer, Wenbin Lu, Carl L. Rodriguez, Mitchell Lachat, Frederic A. Rasio

Research output: Contribution to journalArticlepeer-review

30 Scopus citations


In a dense stellar environment, such as the core of a globular cluster (GC), dynamical interactions with black holes (BHs) are expected to lead to a variety of astrophysical transients. Here we explore tidal disruption events (TDEs) of stars by stellar-mass BHs through collisions and close encounters. Using state-of-the-art cluster simulations, we show that these TDEs occur at significant rates throughout the evolution of typical GCs and we study how their relative rates relate to cluster parameters such as mass and size. By incorporating a realistic cosmological model of GC formation, we predict a BH-main-sequence-star TDE rate of approximately 3 Gpc-3 yr-1 in the local universe (z < 0.1) and a cosmological rate that peaks at roughly 25 Gpc-3 yr-1 for redshift 3. Furthermore, we show that the ejected mass associated with these TDEs could produce optical transients of luminosity ∼1041-1044 erg s-1 with timescales of about a day to a month. These should be readily detectable by optical transient surveys such as the Zwicky Transient Facility. Finally, we comment briefly on BH-giant encounters and discuss how these events may contribute to the formation of BH-white-dwarf binaries.

Original languageEnglish (US)
Article number75
JournalAstrophysical Journal
Issue number1
StatePublished - Aug 10 2019


  • globular clusters: general
  • methods: numerical
  • stars: black holes
  • stars: kinematics and dynamics

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'Tidal Disruptions of Stars by Black Hole Remnants in Dense Star Clusters'. Together they form a unique fingerprint.

Cite this