2018年1月9日 | 新着情報
Lecturer: Koutarou Kyutoku (KEK)
Date/Time: January 17th (Wed), 2018, 16:00-
Place: Conference Room B (1F), Center for Computational Sciences, University of Tsukuba
Abstract: The last year has witnessed a spectacular opening of multimessenger astronomy with binary neutron star mergers. Gravitational waves from the binary neutron star merger, GW170817, are detected by the LIGO-Virgo collaboration. They informed us that neutron stars should be moderately compact (say, smaller than 13-14km). A nominal short gamma-ray burst, GRB170817A, were detected by Fermi and INTEGRAL satellites at 2sec after merger. This detection confirmed that binary-neutron-star mergers can drive a kind of short gamma-ray bursts, although this event was not a typical gamma-ray burst involving an ultrarelativistic jet. An ultraviolet/optical/infrared transient, AT 2017gfo, is observed by a follow-up campaign by many telescopes. This transient was not similar to any other transients those have been discovered and is largely consistent with a predicted marcronova/kilonova, quasithermal radiation powered by the decay of r-process elements synthesized in the material ejected during binary neutron star mergers. Thus, binary-neutron-star mergers are likely to synthesize r-process elements. In this seminar, I will review this event focusing mainly on gravitational waves and the macronova/kilonova.