Dynamical bar instability in a relativistic rotational core collapse

Abstract

We investigate the rotational core collapse of a rapidly rotating relativistic star by means of a 3+1 hydrodynamical simulations in conformally flat spacetime of general relativity. We concentrate our investigation to the bounce of the rotational core collapse, since potentially most of the gravitational waves from it are radiated around the core bounce. The dynamics of the star is started from a differentially rotating equilibrium star of T/W ~ 0.16 (T is the rotational kinetic energy and W is the gravitational binding energy of the equilibrium star), depleting the pressure to initiate the collapse and to exceed the threshold of dynamical bar instability. Our finding is that the collapsing star potentially forms a bar when the star has a toroidal structure due to the redistribution of the angular momentum at the core bounce. On the other hand, the collapsing star weakly forms a bar when the star has a spheroidal structure. We also find that the bar structure of the star is destroyed when the torus is destroyed in the rotational core collapse. Since the collapse of a toroidal star potentially forms a bar, it can be a promising source of gravitational waves which will be detected in advanced LIGO.

12 pages with 8 figures, revtex4.cls. Physical Review D71, 104038 (2005)

References in corpus (29)

• Simulation of merging binary neutron stars in full general relativity: $\Gamma =2$ case
• Core-Collapse Simulations of Rotating Stars
• Gravitational Wave Emission From Core-Collapse of Massive Stars
• Towards Gravitational Wave Signals from Realistic Core Collapse Supernova Models
• Merger of binary neutron stars of unequal mass in full general relativity
• Relativistic simulations of rotational core collapse. I. Methods, initial models, and code tests
• The bar-mode instability in differentially rotating neutron stars: Simulations in full general relativity
• Gravitational Waves from Axisymmetric, Rotational Stellar Core Collapse
• Gravitational Waves from the Merger of Binary Neutron Stars in a Fully General Relativistic Simulation
• Dynamical instability of differentially rotating stars
• Nonlinear Pulsations in Differentially Rotating Neutron Stars: Mass-Shedding-Induced Damping and Splitting of the Fundamental Mode
• Three-dimensional simulations of stellar core collapse in full general relativity: Nonaxisymmetric dynamical instabilities
• Dynamical bar-mode instability of differentially rotating stars: Effects of equations of state and velocity profiles
• Axisymmetric general relativistic hydrodynamics: Long-term evolution of neutron stars and stellar collapse to neutron stars and black holes
• Gravitational waves from axisymmetric rotating stellar core collapse to a neutron star in full general relativity
• One-Armed Spiral Instability in Differentially Rotating Stars
• Gravitational Radiation from Axisymmetric Rotational Core Collapse
• Gravitational Waves from Long-Duration Simulations of the Dynamical Bar Instability
• Gravitational Radiation from Nonaxisymmetric Instability in a Rotating Star
• Gravitational waves from relativistic rotational core collapse
• Relativistic Hydrodynamic Evolutions with Black Hole Excision
• Axisymmetric core collapse simulations using characteristic numerical relativity
• Dynamical Bar Instability in Rotating Stars: Effect of General Relativity
• Models of Rapidly Rotating Neutron Stars: Remnants of Accretion Induced Collapse
• Simulations of non-axisymmetric rotational core collapse
• Simulations of Nonaxisymmetric Instability in a Rotating Star: A Comparison Between Eulerian and Smooth Particle Hydrodynamics
• Dynamical instability of new-born neutron stars as sources of gravitational radiation
• Gravitational Radiation from Rotational Instabilities in Compact Stellar Cores with Stiff Equations of State
• The Collapse of Differentially Rotating Supermassive Stars: Conformally Flat Simulations

Cited by in corpus (8)

• Accurate simulations of the dynamical bar-mode instability in full General Relativity
• Parametrized 3D models of neutrino-driven supernova explosions: Neutrino emission asymmetries and gravitational-wave signals
• Non-linear axisymmetric pulsations of rotating relativistic stars in the conformal flatness approximation
• Dynamical non-axisymmetric instabilities in rotating relativistic stars
• Low T/|W| dynamical instability in differentially rotating stars: Diagnosis with canonical angular momentum
• AMR simulations of the low T/|W| bar-mode instability of neutron stars
• Non-axisymmetric instability and fragmentation of general relativistic quasi-toroidal stars
• A Black-Hole Excision Scheme for General Relativistic Core-Collapse Supernova Simulations