Eccentric Black Hole-Neutron Star Mergers

Frans Pretorius

April 19, 2012

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Abstract: Binary compact object mergers are among the primary gravitational wave sources expected to be observed by the next generation of ground-based gravitational wave detectors. Mergers where one or both compact objects are neutron stars will further produce electromagnetic emission, and coincident observation of this together with gravitational wave emission could teach us much about the progenitor systems, test general relativity in the dynamical strong field regime, and help elucidate the nature of matter at nuclear density. I will discuss some ongoing work modeling such mergers within the context of general relativity coupled to ideal hydrodynamics, focusing on black hole-neutron star systems merging with sizable eccentricity. Large eccentricity at merger is expected for mergers that occur via dynamical capture in dense cluster environments, and though they may be rarer than traditional quasi circular inspiral events, they could exhibit strikingly different behavior, including zoom-whirl orbital dynamics and large amounts of unbound material for cases where the neutron star is tidally disrupted.