Strong-field gravitational-wave emission in Schwarzschild and Kerr geometries: some general considerations

¹ ICRANet, Piazza della Repubblica 10, I–65122 Pescara, Italy
² Dipartimento di Fisica and ICRA, Sapienza Università di Roma, P.le Aldo Moro 5, I–00185 Rome, Italy

^* e-mail: jose.rodriguez@icranet.org
^** e-mail: jorge.rueda@icra.it
^*** e-mail: ruffini@icra.it

Published online: 9 January 2018

Abstract

We have used the perturbations of the exact solutions of the Einstein equations to estimate the relativistic wave emission of a test particle orbiting around a black hole. We show how the hamiltonian equations of motion of a test particle augmented with the radiation-reaction force can establish a priori constraints on the possible phenomena occurring in the merger of compact objects. The dynamical evolution consists of a helicoidal sequence of quasi-circular orbits, induced by the radiation-reaction and the background spacetime. Near the innermost stable circular orbit the evolution is followed by a smooth transition and finally plunges geodesically into the black hole horizon. This analysis gives physical insight of the merger of two equal masses objects.