2017/10/31 by Hao Wang, Fu-Wen Zhang, Yuan-Zhu Wang +9 · 4 citations
Earth and Planetary Sciences · Physics and Astronomy · #Binary number #COSMIC cancer database #Earth Systems and Cosmic Evolution #Galaxy #Gamma-ray burst #Gamma-ray bursts and supernovae #Gravitational wave #LIGO #Neutron star #Pulsars and Gravitational Waves Research #Superluminal motion #Supernova #astro-ph.HE #gr-qc
paper · pdf · doi:10.3847/2041-8213/aa9e08
8 pages, 3 figures, Accepted for Publication in ApJL
openalex created_date 2017/11/10 · arxiv created 2017/12/04 · openalex publication_date 2017/12/08 · arxiv updated 2017/12/20 · openalex updated_date 2026/08/05
Abstract On 2017 August 17, a gravitational-wave event (GW170817) and an associated short gamma-ray burst (GRB 170817A) from a binary neutron star merger had been detected. The follow-up optical/infrared observations also identified the macronova/kilonova emission (AT 2017gfo). In this work, we discuss some implications of the remarkable GW170817/GRB 170817A/AT 2017gfo association. We show that the ∼1.7 s time delay between the gravitational-wave (GW) and GRB signals imposes very tight constraints on the superluminal movement of gravitational waves (i.e., the relative departure of GW velocity from the speed of light is ) or the possible violation of the weak equivalence principle (i.e., the difference of the gamma-ray and GW trajectories in the gravitational field of the galaxy and the local universe should be within a factor of ). The so-called Dark Matter Emulators and a class of contender models for cosmic acceleration (“Covariant Galileon”) are ruled out as well. The successful identification of lanthanide elements in the macronova/kilonova spectrum also excludes the possibility that the progenitors of GRB 170817A are a binary strange star system. The high neutron star merger rate (inferred from both the local sGRB data and the gravitational-wave data) together with the significant ejected mass strongly suggest that such mergers are the prime sites of heavy r -process nucleosynthesis.