Analytical Calculation of the Mergers of Black Hole-Neutron Star Binaries

作者：Cho Hee Suk^*; Lee Chang Hwan

来源：Publications of the Astronomical Society of Japan, 2010, 62(2): 315-321.

DOI：10.1093/pasj/62.2.315

• black hole physics
• stars: neutron
• stars: binaries (including multiple): close
• gamma rays: theory

Black hole (BH)-neutron star (NS) mergers have been studied as one of the primary sources of gravitational wave radiation and a strong candidate for the sources of short-hard gamma-ray bursts (SHBs). In this work, we investigated the criterion for a tidal disruption to occur outside the innermost stable circular orbit with various initial conditions of BH and NS. We studied the merger processes due to Roche-lobe overflow by an analytical method with Newtonian orbital functions. By using the polytropic equation of state for the NS, we calculated the time scale of merger for both irrotating (IR) and corotationg (CR) configurations. The resulting time scale is similar to 10(-3)s for the IR case, which agrees well with that of hydrodynamic simulations. We present a simple comparison with the most recent simulation result. The connection to the SHBs is also discussed.

• 出版日期2010