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Abstract Tidal disruption events (TDEs) are a class of transients that occur when a star is destroyed by the tides of a massive black hole (MBH). Their rates encode valuable MBH demographic information, but this can only be extracted if accurate TDE rate predictions are available for comparisons with observed rates. In this work, we present a new, observer-friendly Python package called REPTiDE, which implements a standard loss-cone model for computing TDE rates given a stellar density distribution and an MBH mass. We apply this software to a representative sample of 91 nearby galaxies over a wide range of stellar masses with high-resolution nuclear density measurements from C. H. Hannah et al. We measure per-galaxy TDE rates ranging between 10−7.7and 10−2.9yr–1and find that the sample-averaged rates agree well with observations. We find a turnover in the TDE rate as a function of both galaxy stellar mass and black hole mass, with the peak rates being observed in galaxies at a galaxy mass of 109.5M⊙and a black hole mass of 106.5M⊙. Despite the lower TDE rates inferred for intermediate-mass black holes, we find that they have gained a higher fraction of their mass through TDEs when compared to higher-mass black holes. This growth of lower-mass black holes through TDEs can enable us to place interesting constraints on their spins; we find maximum spins ofa• ≈ 0.9 for black holes with masses below ∼105.5M⊙.
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This content will become publicly available on May 6, 2026
Little Red Dots Are Tidal Disruption Events in Runaway-collapsing Clusters
Abstract I hypothesize a physical explanation for the “little red dots” (LRDs) discovered by the James Webb Space Telescope (JWST). The first star formation in the Universe occurs in dense clusters, some of which may undergo runaway collapse and form an intermediate mass black hole. This process would appear as a very dense stellar system, with recurring tidal disruption events (TDEs) as stellar material is accreted by the black hole. Such a system would be compact, UV-emitting, and exhibit broad Hαemission. If runaway collapse is the primary mechanism for forming massive black hole seeds, this process could be fairly common and explain the large volume densities of LRDs. In order to match the predicted number density of runaway collapse clusters, the tidal disruption rate must be on the order of 10−4per year. A top-heavy stellar initial mass function may be required to match observations without exceeding the predicted ΛCDM mass function. The TDE LRD hypothesis can be verified with follow-up JWST observations looking for TDE-like variability.
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- Award ID(s):
- 2107764
- PAR ID:
- 10635363
- Publisher / Repository:
- Astrophysical Journal Letters
- Date Published:
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 984
- Issue:
- 2
- ISSN:
- 2041-8205
- Page Range / eLocation ID:
- L55
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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