Axisymmetric Simulations of Rotating Stellar Collapse in Full General Relativity --- Criteria for Prompt Collapse to Black Holes

Astronomy and Astrophysics – Astrophysics – General Relativity and Quantum Cosmology

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

41 pages, to appear in Prog. Theor. Phys. 104, August

Scientific paper

10.1143/PTP.104.325

Motivated by a recent paper by the Potsdam numerical relativity group, we have constructed a new numerical code for hydrodynamic simulation of axisymmetric systems in full general relativity. In this code, we solve the Einstein field equation using Cartesian coordinates with appropriate boundary conditions. On the other hand, the hydrodynamic equations are solved in cylindrical coordinates. Using this code, we perform simulations to study axisymmetric collapse of rotating stars, which thereby become black holes or new compact stars, in full general relativity. To investigate the effects of rotation on the criterion for prompt collapse to black holes, we first adopt a polytropic equation of state, $P=K\rho^{\Gamma}$, where $P$, $\rho$, and $K$ are the pressure, rest mass density, and polytropic constant, with $\Gamma=2$. In this case, the collapse is adiabatic (i.e., no change in entropy), and we can focus on the bare effect of rotation. As the initial conditions, we prepare rigidly and differentially rotating stars in equilibrium and then decrease the pressure to induce collapse. In this paper, we consider cases in which $q \equiv J/M_g^2 < 1$, where $J$ and $M_g$ are the angular momentum and the gravitational mass. It is found that the criterion of black hole formation is strongly dependent on the angular momentum parameter $q$. For $q < 0.5$, the criterion is not strongly sensitive to $q$; more precisely, if the rest mass is slightly larger than the maximum allowed value of spherical stars, a black hole is formed. However, for $q \alt 1$, it changes significantly: For $q \simeq 0.9$, the maximum allowed rest mass becomes $\sim 70$ - 80% larger than that for spherical stars.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Axisymmetric Simulations of Rotating Stellar Collapse in Full General Relativity --- Criteria for Prompt Collapse to Black Holes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Axisymmetric Simulations of Rotating Stellar Collapse in Full General Relativity --- Criteria for Prompt Collapse to Black Holes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Axisymmetric Simulations of Rotating Stellar Collapse in Full General Relativity --- Criteria for Prompt Collapse to Black Holes will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-631077

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.