Astronomy and Astrophysics – Astrophysics – General Relativity and Quantum Cosmology
Scientific paper
2012-02-06
Astronomy and Astrophysics
Astrophysics
General Relativity and Quantum Cosmology
11 pages, 7 figures
Scientific paper
We examine numerically the process of gravitational wave recoil in the merger of two black holes in non head-on collision, in the realm of Robinson-Trautman spacetimes. Characteristic initial data for the system are constructed, and the evolution covers the post-merger phase up to the final configuration of the remnant black hole. The net momentum flux carried out by gravitational waves and the associated impulses are evaluated. Our analysis is based on the Bondi-Sachs conservation laws for the energy momentum of the system. The net kick velocity $V_{k}$ imparted to the merged system by the total gravitational wave impulse is also evaluated. Typically for a non head-on collision the net momentum flux carried out by gravitational waves is nonzero for equal-mass colliding black holes. The distribution of $V_{k}$ as a function of the symmetric mass ratio $\eta$ is well fitted by a modified Fitchett $\eta$-scaling law, the additional parameter modifying the law being a measure of the nonzero gravitational wave momentum flux for equal-mass initial black holes. For an initial infalling velocity $v/c \simeq 0.462$ of the colliding black holes, and incidence angle of collision $\rho_0=21^{o}$, we obtain a maximum $V_{k} \sim 121 {\rm km/s}$ located at $\eta \simeq 0.226$. For initial equal-mass black holes ($\eta=0.25$) we obtain $V_{k} \sim 107 {\rm km/s}$. Based on the integrated Bondi-Sachs momentum conservation law we discuss a possible definition of the center-of-mass velocity of the binary merged system and show that -- in an appropriate inertial frame -- it approaches asymptotically the net kick velocity, which is the velocity of the remnant black hole in this inertial frame. For larger values of $v/c$ we obtain substantially larger values of the net kick velocity, e.g., for $v/c \simeq 0.604$ a maximum $V_{k} \sim 610 {\rm km/s}$ is obtained.
Aranha R. F.
Damio Soares I.
Tonini E. V.
No associations
LandOfFree
Gravitational Wave Recoil and Kick Processes in the Merger of Two Colliding Black Holes: The Non Head-on Case 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 Gravitational Wave Recoil and Kick Processes in the Merger of Two Colliding Black Holes: The Non Head-on Case, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Gravitational Wave Recoil and Kick Processes in the Merger of Two Colliding Black Holes: The Non Head-on Case will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-578146