Pith sign in

REVIEW 8 cited by

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 1906.10260 v2 pith:RA4ICJ5A submitted 2019-06-24 astro-ph.HE gr-qc

Black Holes: The Next Generation -- Repeated Mergers in Dense Star Clusters and their Gravitational-Wave Properties

classification astro-ph.HE gr-qc
keywords blackholesmergersclustersstarbirthdensehole
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
read the original abstract

When two black holes merge in a dense star cluster, they form a new black hole with a well-defined mass and spin. If that "second-generation" black hole remains in the cluster, it will continue to participate in dynamical encounters, form binaries, and potentially merge again. Using a grid of 96 dynamical models of dense star clusters and a cosmological model of cluster formation, we explore the production of binary black hole mergers where at least one component of the binary was forged in a previous merger. We create four hypothetical universes where every black hole born in the collapse of a massive star has a dimensionless Kerr spin parameter, $\chi_{\rm birth}$, of 0.0, 0.1, 0.2, or 0.5. We show that if all stellar-born black holes are non-spinning ($\chi_{\rm birth} = 0.0$), then more than 10% of merging binary black holes from clusters have components formed from previous mergers, accounting for more than 20% of the mergers from globular clusters detectable by LIGO/Virgo. Furthermore, nearly 7% of detectable mergers would have a component with a mass $\gtrsim 55M_{\odot}$, placing them clearly in the mass "gap" region where black holes cannot form from isolated collapsing stars due to the pulsational-pair instability mechanism. On the other hand, if black holes are born spinning, then the contribution from these second-generation mergers decreases, making up as little as 1% of all detections from globular clusters when $\chi_{\rm birth} = 0.5$. We make quantitative predictions for the detected masses, mass ratios, and spin properties of first- and second-generation mergers from dense star clusters, and show how these distributions are highly sensitive to the birth spins of black holes.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 8 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Second-Generation Mass Peak in the Gravitational-Wave Population as a Probe of Globular Clusters

    astro-ph.HE 2026-04 unverdicted novelty 6.0

    Dynamical formation in globular clusters produces a robust second black-hole mass peak at ~70 solar masses from second-generation mergers when the first-generation spectrum is truncated by pair-instability supernovae.

  2. Posterior Predictive Checks for Gravitational-wave Populations: Limitations and Improvements

    gr-qc 2026-04 unverdicted novelty 6.0

    Maximum-likelihood-based posterior predictive checks detect model misspecification better than event-level versions for uncertain spin tilts, but current detector sensitivity limits their power; the Gaussian Component...

  3. Signatures of a subpopulation of hierarchical mergers in the GWTC-4 gravitational-wave dataset

    gr-qc 2026-01 unverdicted novelty 6.0

    GWTC-4 data show a transition to nearly all hierarchical mergers above 46 solar masses, with the hierarchical rate peaking at 15.7 solar masses, indicating mass-dependent substructure in black hole spins.

  4. Spin-up and mass-gain in hyperbolic encounters of spinning black holes

    gr-qc 2025-10 unverdicted novelty 6.0

    Numerical relativity simulations of equal-mass black holes with initial spins from -0.7 to 0.7 in hyperbolic encounters find maximum spin-up of 0.3 and mass increase of 15%, with spin-up decreasing linearly with initi...

  5. GW231123: A Possible Primordial Black Hole Origin

    astro-ph.CO 2025-08 conditional novelty 6.0

    GW231123's masses and high spins are consistent with primordial black holes that accreted mass and angular momentum in the early universe within the standard PBH framework.

  6. A Possible Triple Formation Scenario of Binary Black Hole Merge With One In Pair-instability Supernova Mass Gap

    astro-ph.HE 2026-07 conditional novelty 5.0

    An isolated hierarchical triple channel with chemically homogeneous evolution and triple common envelope can produce PISN mass-gap BBH mergers matching GW190706 at ~22% of the observed rate.

  7. Evidence for additional structure in the effective spin distribution hints at multiple formation pathways in GWTC-5.0

    astro-ph.HE 2026-06 unverdicted novelty 4.0

    GWTC-5.0 analysis finds evidence for structure beyond a non-skewed Gaussian bulk in χ_eff, with suggestive mass-dependent excess of positive over negative spins outside the bulk at 13:1 odds in one mass bin.

  8. GWTC-2.1: Deep Extended Catalog of Compact Binary Coalescences Observed by LIGO and Virgo During the First Half of the Third Observing Run

    gr-qc 2021-08 accept novelty 4.0

    GWTC-2.1 adds eight new high-significance compact binary coalescence events to the prior catalog, extending the observed black hole mass range and including candidates inside the pair-instability mass gap.