1. The X-ray counterpart to the gravitational-wave event GW170817
- Author
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Troja, E, Piro, L, Van Eerten, H, Wollaeger, RT, Im, M, Fox, OD, Butler, NR, Cenko, SB, Sakamoto, T, Fryer, CL, Ricci, R, Lien, A, Ryan, RE, Korobkin, O, Lee, SK, Burgess, JM, Lee, WH, Watson, AM, Choi, C, Covino, S, D'Avanzo, P, Fontes, CJ, Becerra González, J, Khandrika, HG, Kim, J, Kim, SL, Lee, CU, Lee, HM, Kutyrev, A, Lim, G, Sánchez-Ramírez, R, Veilleux, S, Wieringa, MH, and Yoon, Y
- Subjects
astro-ph.HE ,General Science & Technology - Abstract
A long-standing paradigm in astrophysics is that collisions-or mergers-of two neutron stars form highly relativistic and collimated outflows (jets) that power γ-ray bursts of short (less than two seconds) duration. The observational support for this model, however, is only indirect. A hitherto outstanding prediction is that gravitational-wave events from such mergers should be associated with γ-ray bursts, and that a majority of these bursts should be seen off-axis, that is, they should point away from Earth. Here we report the discovery observations of the X-ray counterpart associated with the gravitational-wave event GW170817. Although the electromagnetic counterpart at optical and infrared frequencies is dominated by the radioactive glow (known as a kilonova') from freshly synthesized rapid neutron capture (r-process) material in the merger ejecta, observations at X-ray and, later, radio frequencies are consistent with a short γ-ray burst viewed off-axis. Our detection of X-ray emission at a location coincident with the kilonova transient provides the missing observational link between short γ-ray bursts and gravitational waves from neutron-star mergers, and gives independent confirmation of the collimated nature of the γ-ray-burst emission.
- Published
- 2017