• DOI:10.3847/2041-8213/aa91c9
• Corpus ID: 217162243

Multi-messenger observations of a binary neutron star merger

@article{Collaboration2017MultimessengerOO,
  title={Multi-messenger observations of a binary neutron star merger},
  author={Ligo Scientific Collaboration and Virgo Collaboration and Fermi Gbm and Integral and IceCube collaboration and AstroSat Cadmium Zinc Telluride Imager Team and Ipn Collaboration and The Insight-Hxmt Collaboration and Antares Collaboration and The Swift Collaboration and Agile Team and The Maxi Team and The Dark Energy Science Collaboration and The Des Collaboration and The DLT40 Collaboration and Grawita GRAvitational Wave Inaf TeAm and The Event Horizon Telescope Collaboration and Atca Australia Telescope Compact Array and A Pathfinder and Las Cumbres Observatory Group and OzGrav and Dwf and AST3 and Caastro Collaborations and The Vinrouge Collaboration and Master Collaboration and J-GEM and Growth and Jagwar and Caltech- Nrao and TTU-NRAO and NuSTAR collaborations and Pan-Starrs and The Maxi Team and Tzac Consortium and KU Collaboration and Nordic Optical Telescope and ePESSTO and Grond and Texas Tech University and Salt Collaborative Group and Toros Transient Robotic Observatory of the South Collaboration and The Bootes Collaboration and Mwa Murchison Widefield Array and The Calet Collaboration and IKI-GW Follow-up Collaboration and Hawc collaboration and Lofar Collaboration and Lwa Long Wavelength Array and Hawc collaboration and The Pierre Auger Collaboration and Almasop collaboration and Euro Vlbi Team and Pi of the Sky Collaboration and The Chandra Team at McGill University and Dfn Desert Fireball Network and Atlas and High Time Resolution Universe Survey and Rimas and Ratir and Ska South AfricaMeerKAT},
  journal={The Astrophysical Journal},
  year={2017},
  volume={848},
  pages={1-59}
}

• L. S. Collaboration, V. Collaboration, +58 authors Ska South AfricaMeerKAT
• Published 16 October 2017
• Physics
• The Astrophysical Journal

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of $\sim 1.7\,{\rm{s}}$ with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of ${40}_{-8}^{+8}$ Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 $\,{M}_{\odot }$. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at $\sim 40\,{\rm{Mpc}}$) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient's position $\sim 9$ and $\sim 16$ days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.