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arXiv · 1105.3302

Afterglow of binary neutron star merger

Masaru Shibata·Yudai Suwa·Kenta Kiuchi·Kunihito Ioka
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Abstract

The merger of two neutron stars results often in a rapidly and differentially rotating hypermassive neutron star (HMNS). We show by numerical-relativity simulation that the magnetic-field profile around such HMNS is dynamically varied during its subsequent evolution, and as a result, electromagnetic radiation with a large luminosity ~ 0.1 B^2 R^3 Omega is emitted with baryon (B, R, and Omega are poloidal magnetic-field strength at stellar surface, stellar radius, and angular velocity of a HMNS). The predicted luminosity of electromagnetic radiation, which is primarily emitted along the magnetic-dipole direction, is ~ 10^{47} (B/10^{13} G)^2(R/10 km)^3(Omega/10^4 rad/s) ergs/s, that is comparable to the luminosity of quasars.

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Masaru Shibata, Yudai Suwa, Kenta Kiuchi, Kunihito Ioka. 2011-05-17. Afterglow of binary neutron star merger. https://doi.org/10.1088/2041-8205%2F734%2F2%2Fl36

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