Heavy-element production in a compact object merger observed by JWST

This paper presents observations of GRB 230307A, an exceptionally bright gamma-ray burst, using the James Webb Space Telescope (JWST). The authors find that GRB 230307A is a long-duration GRB associated with a compact object merger, containing a kilonova similar to AT2017gfo. JWST mid-infrared imaging and spectroscopy reveal an emission line interpreted as tellurium and a very red source, indicating the production of lanthanides. These findings demonstrate the creation of r-process elements across a broad atomic mass range in GRBs and their crucial role in heavy-element nucleosynthesis.

Andrew J. Levan, Benjamin P. Gompertz, Owen Shanar, Mat Bulat, Eric Burns, Kenta Hotezuka, Luca Izzo, Gavin P. Lamb, Daniele B. Malesani, Samantha R. Oates, Maria Edvige Ravasio, Alicia R. Bosco Escorial, Benjamin Schneider, Nikhil Sarin, Steve Schulze, Nial R. Tanvir, Kendal Ackley, Gemma Anderson, Gabriel B. Brammer, Lise Christensen, Vikram S. Dhillon, Filippo Mannucci, Michael Fausnaught, Wen-fai Fong, Andrew S. Fruchter, Chris Fryer, Johan P. U. Fynbo, Nicola Gasparri, Kasper E. Heintz, Jens Hjorth, Jamie A. Kennea, Mark R. Kennedy, Tannoy Laskar, Giorgio Leobardo, Lisa Mandel, Antonio Martín-Carrión, Brian D. Metzger, Atti Nicholl, Anya Nugent, Jesse T. Palmer, Giovanna Pugliese, Jillian Restadini, Lauren Rhodes, Andrea Rossi, Andrea Saccardi, Stephen J. Smartt, Heloise F. Stevance, Aaron Tohuvavohu, Alexander van der Horst, Susan E. Vergani, Darch Watson, Thomas Barclay, Korob Bhirbhadak, Émile Breedt, Alice A. Breveld, Alexander J. Brown, Sergio Campana, Ashley C. Franks, Paolo D'Avanzo, Valerio D'Elia, Massimiliano De Pasquale, Martin J. Dyer, Duncan K. Galloway, James A. Garùa, Matthew J. Green, Dieter H. Hartmann, Palm Jäkel, Chrysa Kouveliotou, Daniel Langerdorff, Emeric Le Floc'h, James K. Leung, Stuart P. Littlefair, James Mundy, Paul O'Brien, Steven G. Parsons, Ingrid Pessah, David I. Sahman, Ruben Salvador, Boris Starrett, Danny Stegman, Gianpiero Tagliapietri, Christina C. Thöne, Antonio de Ugarte Postigo, David Alexander Kann