Illuminating gravitational waves: A concordant picture of photons from a neutron star merger.
Mansi M KasliwalE NakarL P SingerDavid L KaplanD O CookA Van SistineR M LauC FremlingO GottliebJ E JencsonS M AdamsU FeindtK HotokezakaS GhoshD A PerleyP-C YuT PiranJ R AllisonG C AnupamaA BalasubramanianKeith W BannisterJ BallyJ BarnesSudhanshu BarwayEric C BellmVarun BhaleraoD BhattacharyaN BlagorodnovaJ S BloomP R BradyC CannellaDeep ChatterjeeS Bradley CenkoB E CobbC CopperwheatA CorsiK DeD DobieS W K EmeryP A EvansO D FoxD A FrailChristopher FrohmaierAriel GoobarG HallinanF A HarrisonGeorge HelouT HindererAnna Y Q HoAssaf HoreshW-H IpR ItohD KasenH KimN P M KuinT KupferC LynchK K MadsenP A MazzaliAdam A MillerKunal P MooleyTara MurphyChow-Choong NgeowD NicholsS NissankeP E NugentE O OfekH QiR M QuimbyS RosswogF RusuE M SadlerPatricia SchmidtJesper SollermanI SteeleA R WilliamsonY XuL YanY YatsuC ZhangW ZhaoPublished in: Science (New York, N.Y.) (2017)
Merging neutron stars offer an excellent laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) with gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic data set, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultrarelativistic jets. Instead, we suggest that breakout of a wide-angle, mildly relativistic cocoon engulfing the jet explains the low-luminosity gamma rays, the high-luminosity ultraviolet-optical-infrared, and the delayed radio and x-ray emission. We posit that all neutron star mergers may lead to a wide-angle cocoon breakout, sometimes accompanied by a successful jet and sometimes by a choked jet.