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R. A. Matzner

Publications and source records attributed to R. A. Matzner.

6 recordsLinked to original sources

The Earth's Frame Dragging via Laser Ranged Satellites: a Response to 'Some considerations on the present-day results for the detection of frame-dragging after the final outcome of GP-B' by L. Iorio [arXiv:1105.4145]

In this note, we reply to the preceding paper by Iorio: "Some considerations on the present-day results for the detection of frame-dragging after the final outcome of GP-B, Europhysics Letters", we address criticisms regarding the Lense-Thirring frame-dragging experiment results obtained from the laser ranging to the two LAGEOS satellites.

gr-qc

Multipole Analysis of Kicks in Collision of Binary Black Holes

Thorne and Kidder give expressions which allow for analytical estimates of the "kick", it i.e. the recoil, produced from asymmetrical gravitational radiation during the interaction of black holes, or in fact any gravitating compact bodies. (The Thorne-Kidder formula uses momentum flux calculations based on the linearized General Relativity of gravitational radiation.) We specifically treat kicks arising in the binary interaction of equal mass black holes, when at least one of the black holes has significant spin, a. Such configurations can produce very large kicks in computational simulations. We consider both fly-by and quasicircular orbits. For fly-by orbits we find substantial kicks from those Thorne-Kidder terms which are linear in a. For the quasi-circular case, we consider in addition the nonlinear contribution (O(a^2)) to the kicks, and provide a dynamical explanation for such terms. However, in the cases of maximal kick velocities, the dependence on spin is largely linear (reproduced in numerical results).

gr-qc

Binary Black Hole Encounters, Gravitational Bursts and Maximum Final Spin

The spin of the final black hole in the coalescence of nonspinning black holes is determined by the ``residual'' orbital angular momentum of the binary. This residual momentum consists of the orbital angular momentum that the binary is not able to shed in the process of merging. We study the angular momentum radiated, the spin of the final black hole and the gravitational bursts in a series of orbits ranging from almost direct infall to numerous orbits before infall that exhibit multiple bursts of radiation in the merger process. We show that the final black hole gets a maximum spin parameter $a/M_h \le 0.78$, and this maximum occurs for initial orbital angular momentum $L \approx M^2_h$.

gr-qc

Boosted three-dimensional black-hole evolutions with singularity excision

Binary black hole interactions provide potentially the strongest source of gravitational radiation for detectors currently under development. We present some results from the Binary Black Hole Grand Challenge Alliance three- dimensional Cauchy evolution module. These constitute essential steps towards modeling such interactions and predicting gravitational radiation waveforms. We report on single black hole evolutions and the first successful demonstration of a black hole moving freely through a three-dimensional computational grid via a Cauchy evolution: a hole moving ~6M at 0.1c during a total evolution of duration ~60M.

gr-qc

Gravitational wave extraction and outer boundary conditions by perturbative matching

We present a method for extracting gravitational radiation from a three-dimensional numerical relativity simulation and, using the extracted data, to provide outer boundary conditions. The method treats dynamical gravitational variables as nonspherical perturbations of Schwarzschild geometry. We discuss a code which implements this method and present results of tests which have been performed with a three dimensional numerical relativity code.

gr-qc