2006/10/31 by Anthony L. Piro, Eric Pfahl · 4 citations
Physics and Astronomy · #Accretion (finance) #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Fragmentation (computing) #Gamma-ray bursts and supernovae #Gravitation #Gravitational collapse #Gravitational energy #Gravitational redshift #Gravitational wave #LIGO #Neutron star #Physics #Pulsars and Gravitational Waves Research #astro-ph
paper · pdf · doi:10.1086/511672
Accepted for publication in The Astrophysical Journal, 5 pages, 2 figures; added noise estimates for enhanced LIGO and expanded discussion of rates
arxiv created 2006/12/15 · openalex publication_date 2007/03/29 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We argue that gravitational instability in the outer parts of collapsar disks may lead to fragmentation near the radius where helium photodisintegrates, because of the strong cooling provided by this process. This physics sets clear physical scales for the fragmentation conditions and the properties of gravitationally bound clumps. Collapse of a fragment proceeds until the neutrons become degenerate; a neutron star of mass ≈0.1-1 M ☉ may result. We find that tidal disruption of a fragment and accretion by the central black hole are too rapid to account for the durations of observed X-ray flares from long gamma-ray bursts. Prior to disruption, migration of the fragment is driven by gravitational radiation and disk viscosity, which act together to produce a unique gravitational wave signature. Advanced LIGO may be able to detect such sources within ≈100 Mpc.