Heavy element production in a compact object merger observed by JWST.
Andrew J LevanBenjamin P GompertzOm Sharan SalafiaMattia BullaEric A BurnsKenta HotokezakaLuca IzzoGavin P LambDaniele B MalesaniSamantha R OatesMaria Edvige RavasioAlicia Rouco EscorialBenjamin SchneiderNikhil SarinSteve SchulzeNial R TanvirKendall AckleyGemma AndersonGabriel B BrammerLise ChristensenVikram S DhillonPhil A EvansMichael FausnaughWen-Fai FongAndrew S FruchterChristopher L FryerJohan P U FynboNicola GaspariKasper E HeintzJens HjorthJamie A KenneaMark R KennedyTanmoy LaskarGiorgos LeloudasIlya MandelAntonio Martin-CarrilloBrian D MetzgerMatt NichollAnya NugentJesse T PalmerioGiovanna PuglieseJillian C RastinejadLauren RhodesAndrea RossiAndrea SaccardiStephen J SmarttHeloise F StevanceAaron TohuvavohuAlexander van der HorstSusanna D VerganiDarach WatsonThomas BarclayKornpob BhirombhakdiElmé BreedtAlice A BreeveldAlexander J BrownSergio CampanaAshley A ChrimesPaolo D'AvanzoValerio D'EliaMassimiliano De PasqualeMartin J DyerDuncan K GallowayJames A GarbuttMatthew J GreenDieter H HartmannPáll JakobssonPaul KerryChryssa KouveliotouDanial LangeroodiEmeric Le Floc'hJames K LeungStuart P LittlefairJames MundayPaul O'BrienSteven G ParsonsIngrid PelisoliDavid I SahmanRuben SalvaterraBoris SbarufattiDanny SteeghsGianpiero TagliaferriChristina C ThöneAntonio de Ugarte PostigoDavid Alexander KannPublished in: Nature (2023)
The mergers of binary compact objects such as neutron stars and black holes are of central interest to several areas of astrophysics, including as the progenitors of gamma-ray bursts (GRBs) 1 , sources of high-frequency gravitational waves (GW) 2 and likely production sites for heavy element nucleosynthesis via rapid neutron capture (the r-process) 3 . Here we present observations of the exceptionally bright gamma-ray burst GRB 230307A. We show that GRB 230307A belongs to the class of long-duration gamma-ray bursts associated with compact object mergers 4-6 , and contains a kilonova similar to AT2017gfo, associated with the gravitational-wave merger GW170817 7-12 . We obtained James Webb Space Telescope mid-infrared (mid-IR) imaging and spectroscopy 29 and 61 days after the burst. The spectroscopy shows an emission line at 2.15 microns which we interpret as tellurium (atomic mass A=130), and a very red source, emitting most of its light in the mid-IR due to the production of lanthanides. These observations demonstrate that nucleosynthesis in GRBs can create r-process elements across a broad atomic mass range and play a central role in heavy element nucleosynthesis across the Universe.