Electromagnetic evidence that SSS17a is the result of a binary neutron star merger

C D Kilpatrick; R J Foley; D Kasen; A Murguia-Berthier; E Ramirez-Ruiz; D A Coulter; M R Drout; A L Piro; B J Shappee; K Boutsia; C Contreras; F Di Mille; B F Madore; N Morrell; Y-C Pan; J X Prochaska; A Rest; C Rojas-Bravo; M R Siebert; J D Simon; N Ulloa

doi:10.1126/science.aaq0073

Electromagnetic evidence that SSS17a is the result of a binary neutron star merger

Science. 2017 Dec 22;358(6370):1583-1587. doi: 10.1126/science.aaq0073. Epub 2017 Oct 16.

Authors

C D Kilpatrick¹, R J Foley², D Kasen^{3

4}, A Murguia-Berthier², E Ramirez-Ruiz^{2

5}, D A Coulter², M R Drout⁶, A L Piro⁶, B J Shappee^{6

7}, K Boutsia⁸, C Contreras⁸, F Di Mille⁸, B F Madore⁶, N Morrell⁸, Y-C Pan², J X Prochaska², A Rest^{9

10}, C Rojas-Bravo², M R Siebert², J D Simon⁶, N Ulloa¹¹

Affiliations

¹ Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064, USA. cdkilpat@ucsc.edu.
² Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064, USA.
³ Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
⁴ Departments of Physics and Astronomy, University of California, Berkeley, CA 94720, USA.
⁵ DARK, Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 Copenhagen, Denmark.
⁶ The Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101, USA.
⁷ Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA.
⁸ Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena, Chile.
⁹ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA.
¹⁰ Department of Physics and Astronomy, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA.
¹¹ Departamento de Física y Astronomía, Facultad de Ciencias, Universidad de La Serena, Cisternas 1200, La Serena, Chile.

PMID: 29038369
DOI: 10.1126/science.aaq0073

Abstract

Eleven hours after the detection of gravitational wave source GW170817 by the Laser Interferometer Gravitational-Wave Observatory and Virgo Interferometers, an associated optical transient, SSS17a, was identified in the galaxy NGC 4993. Although the gravitational wave data indicate that GW170817 is consistent with the merger of two compact objects, the electromagnetic observations provide independent constraints on the nature of that system. We synthesize the optical to near-infrared photometry and spectroscopy of SSS17a collected by the One-Meter Two-Hemisphere collaboration, finding that SSS17a is unlike other known transients. The source is best described by theoretical models of a kilonova consisting of radioactive elements produced by rapid neutron capture (the r-process). We conclude that SSS17a was the result of a binary neutron star merger, reinforcing the gravitational wave result.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.