학술논문
Swift and NuSTAR Observations of GW170817: Detection of a Blue Kilonova
Document Type
Report
Author
Evans, P. A; Cenko, S. B; Kennea, J. A; Emery, S. W. K; Kuin, N. P. M; Korobkin, O; Wollaeger, R. T; Fryer, C. L; Madsen, K. K; Harrison, F. A; Xu, Y; Nakar, E; Hotokezaka, K; Lien, A; Campana, S; Oates, S. R; Troja, E; Breeveld, A. A; Marshall, F. E; Barthelmy, S. D; Beardmore, A. P; Burrows, D. N; Cusumano, G; D’A, A; D’Avanzo, P; D’Elia, V; de Pasquale, M; Even, W. P; Fontes, C. J; Forster, K; Garcia, J; Giommi, P; Grefenstette, B; Gronwall, C; Hartmann, D. H; Heida, M; Hungerford, A. L; Kasliwal, M. M; Krimm, H. A; Levan, A. J; Malesani, D; Melandri, A; Miyasaka, H; Nousek, J. A; O’Brien, P. T; Osborne, J. P; Pagani, C; Page, K. L; Palmer, D. M; Perri, M; Pike, S; Racusin, J. L; Rosswog, S; Siegel, M. H; Sakamoto, T; Sbarufatti, B; Tagliaferri, G; Tanvir, N. R; Tohuvavohu, A
Source
Science. 358(6370)
Subject
Language
English
ISSN
1095-9203
0036-8075
0036-8075
Abstract
With the first direct detection of merging black holes in 2015, the era of gravitational wave (GW) astrophysics began. A complete picture of compact object mergers, however, requires the detection of an electromagnetic (EM) counterpart. We report ultraviolet (UV) and x-ray observations by Swift and the Nuclear Spectroscopic Telescope Array of the EM counter part of the binary neutron star merger GW170817.The bright, rapidly fading UV emission indicates a high mass (0.03 solar masses) wind-driven outflow with moderate electron fraction (Ye ≈ 0.27). Combined with the x-ray limits, we favor an observer viewing angle of ≈30° away from the orbital rotation axis, which avoids both obscuration from the heaviest elements in the orbital plane and a direct view of any ultra relativistic, highly collimated ejecta (a gamma-ray burst afterglow).