Black Hole-Neutron Star Mergers with a Hot Nuclear Equation of State: Outflow and Neutrino-cooled Disk for a Low-mass, High-spin Case
Abstract
Neutrino emission significantly affects the evolution of the accretion tori formed in black hole-neutron star mergers. It removes energy from the disk, alters its composition, and provides a potential power source for a gamma-ray burst. To study these effects, simulations in general relativity with a hot microphysical equation of state (EOS) and neutrino feedback are needed. We present the first such simulation, using a neutrino leakage scheme for cooling to capture the most essential effects and considering a moderate mass (1.4 M_☉ neutron star, 5.6 M_☉ black hole), high-spin (black hole J/M^2 = 0.9) system with the K_0 = 220 MeV Lattimer-Swesty EOS. We find that about 0.08 M_☉ of nuclear matter is ejected from the system, while another 0.3 M_☉ forms a hot, compact accretion disk. The primary effects of the escaping neutrinos are (1) to make the disk much denser and more compact, (2) to cause the average electron fraction Ye of the disk to rise to about 0.2 and then gradually decrease again, and (3) to gradually cool the disk. The disk is initially hot (T ~ 6 MeV) and luminous in neutrinos (L_ν ~ 10^54 erg s^–1), but the neutrino luminosity decreases by an order of magnitude over 50 ms of post-merger evolution.
Additional Information
© 2013 The American Astronomical Society. Received 2013 April 25; accepted 2013 September 4; published 2013 September 24. We acknowledge helpful discussions with J. Lattimer, L. Roberts, and S. Teukolsky. This research is supported in part by NASA ATP grant No. NNX11AC37G, by the National Science Foundation under grand Nos.PHY-1068243,PHY-106881, PHY-1151197, and AST-1205732, by the Alfred P. Sloan Foundation, and by the Sherman Fairchild Foundation. The computations were performed at Caltech's Center for Advanced Computing Research on the cluster "Zwicky" funded through NSF grant no. PHY-0960291 and the Sherman Fairchild Foundation. Furthermore, computations were performed on the General Purpose Cluster supercomputer at the SciNet HPC Consortium. SciNet is funded by: the Canada Foundation for Innovation under the auspices of Compute Canada; the Government of Ontario; Ontario Research Fund–Research Excellence; and the University of Toronto (Loken et al. 2010).Attached Files
Published - 0004-637X_776_1_47.pdf
Submitted - 1304.3384v2.pdf
Erratum - apj_824_1_62.pdf
Files
Additional details
- Eprint ID
- 42194
- Resolver ID
- CaltechAUTHORS:20131101-114026087
- NASA ATP
- NNX11AC37G
- NSF
- PHY-1068243
- NSF
- PHY-106881
- NSF
- PHY-1151197
- NSF
- AST-1205732
- Alfred P. Sloan Foundation
- Sherman Fairchild Foundation
- NSF
- PHY-0960291
- Canada Foundation for Innovation
- Government of Ontario
- Ontario Research Fund–Research Excellence
- University of Toronto
- Created
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2013-11-01Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field