Theoretical support for the hydrodynamic mechanism of pulsar kicks
The collapse of a massive star's core, followed by a neutrino-driven, asymmetric supernova explosion, can naturally lead to pulsar recoils and neutron star kicks. Here, we present a two-dimensional, radiation-hydrodynamic simulation in which core collapse leads to significant acceleration of a fully formed, nascent neutron star via an induced, neutrino-driven explosion. During the explosion, an ~10% anisotropy in the low-mass, high-velocity ejecta leads to recoil of the high-mass neutron star. At the end of our simulation, the neutron star has achieved a velocity of ~150 km s^(-1) and is accelerating at ~350 km s^(-2), but has yet to reach the ballistic regime. The recoil is due almost entirely to hydrodynamical processes, with anisotropic neutrino emission contributing less than 2% to the overall kick magnitude. Since the observed distribution of neutron star kick velocities peaks at ~300–400 km s^(-1), recoil due to anisotropic core-collapse supernovae provides a natural, nonexotic mechanism with which to obtain neutron star kicks.
Additional Information© 2010 American Physical Society. Received 4 October 2010; published 30 November 2010. J. N. and A. B. are supported by the Scientific Discovery Through Advanced Computing (SciDAC) program of the DOE, under Contract No. DE-FG02-08ER41544, the NSF under Subcontract No. ND201387 to the Joint Institute for Nuclear Astrophysics (JINA, NSF Contract No. PHY-0822648), and the NSF PetaApps program, under Contract No. OCI-0905046 via Subcontract No. 44592 from Louisiana State University to Princeton University. Computational resources were provided by the TIGRESS high-performance computer center at Princeton University, the National Energy Research Scientific Computing Center (NERSC) under Contract No. DE-AC03-76SF00098, and on the Kraken and Ranger supercomputers, hosted at NICS and TACC via TeraGrid Contract No. TG-AST100001. This material is based upon work by T. D. B. supported by the National Science Foundation. C. D. O. is partially supported by the NSF under Contract Nos. AST-0855535 and OCI-0905046.
Published - Nordhaus2010p13882Phys_Rev_D.pdf