Compact Object Mergers and Micro-Tidal Disruption Events: A Multi-Messenger Probe of Dense Stellar Environments
Abstract
Dense stellar environments such as globular clusters and young massive clusters produce both compact-object mergers detectable in gravitational waves and tidal disruption events observable electromagnetically. We investigate compact-object mergers, tidal disruption events, and micro-tidal disruption events (μTDEs) in these environments using rapid Monte Carlo star-cluster simulations with the Rapster code, extended with a unified treatment of neutron-star (NS) and black-hole (BH) spin evolution under disk accretion across the NS-to-BH transition, as well as new dynamical channels for disruptions by single compact objects and by BH-BH binaries. Simulating 105 clusters across ten model variations and two formation histories, we find a BH-BH merger-rate density peaking at z≈2-$3$ at several tens Gpc−3 yr−1, consistent with the local LVK rate, while the cumulative number of μTDEs exceeds that of mergers by a factor of a few. Since we include only dynamically formed binaries, ≈90% of μTDEs proceed through single compact-object-star encounters, and our rates are conservative lower limits. Prograde accretion during μTDEs spins up compact objects, providing a purely dynamical, randomly oriented pathway for producing high-spin BHs, and can drive accretion-induced collapse of NSs to BHs that populate the lower mass gap.
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BibTeX
@misc{kritos2026compact,
title = {{Compact Object Mergers and Micro-Tidal Disruption Events: A Multi-Messenger Probe of Dense Stellar Environments}},
author = {Konstantinos Kritos and Francesco Iacovelli and Rosalba Perna and Emanuele Berti},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.26878},
eprint = {2609.26878},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.26878},
}
RIS
TY - UNPB
TI - Compact Object Mergers and Micro-Tidal Disruption Events: A Multi-Messenger Probe of Dense Stellar Environments
AU - Konstantinos Kritos
AU - Francesco Iacovelli
AU - Rosalba Perna
AU - Emanuele Berti
PY - 2026
DA - 2026/09/22
PB - arXiv
DO - 10.48550/arxiv.2609.26878
UR - https://arxiv.org/abs/2609.26878
AB - Dense stellar environments such as globular clusters and young massive clusters produce both compact-object mergers detectable in gravitational waves and tidal disruption events observable electromagnetically. We investigate compact-object mergers, tidal disruption events, and micro-tidal disruption events (μTDEs) in these environments using rapid Monte Carlo star-cluster simulations with the Rapster code, extended with a unified treatment of neutron-star (NS) and black-hole (BH) spin evolution under disk accretion across the NS-to-BH transition, as well as new dynamical channels for disruptions by single compact objects and by BH-BH binaries. Simulating 10^5 clusters across ten model variations and two formation histories, we find a BH-BH merger-rate density peaking at z≈2-$3$ at several tens Gpc^−3 yr^−1, consistent with the local LVK rate, while the cumulative number of μTDEs exceeds that of mergers by a factor of a few. Since we include only dynamically formed binaries, ≈90% of μTDEs proceed through single compact-object-star encounters, and our rates are conservative lower limits. Prograde accretion during μTDEs spins up compact objects, providing a purely dynamical, randomly oriented pathway for producing high-spin BHs, and can drive accretion-induced collapse of NSs to BHs that populate the lower mass gap.
ER -