title: A very energetic supernova associated with the gamma-ray burst of 29 March 2003.
abstract: Over the past five years evidence has mounted that long-duration (>2 s) gamma-ray bursts (GRBs)-the most luminous of all astronomical explosions-signal the collapse of massive stars in our Universe. This evidence was originally based on the probable association of one unusual GRB with a supernova, but now includes the association of GRBs with regions of massive star formation in distant galaxies, the appearance of supernova-like 'bumps' in the optical afterglow light curves of several bursts and lines of freshly synthesized elements in the spectra of a few X-ray afterglows. These observations support, but do not yet conclusively demonstrate, the idea that long-duration GRBs are associated with the deaths of massive stars, presumably arising from core collapse. Here we report evidence that a very energetic supernova (a hypernova) was temporally and spatially coincident with a GRB at redshift z = 0.1685. The timing of the supernova indicates that it exploded within a few days of the GRB, strongly suggesting that core-collapse events can give rise to GRBs, thereby favouring the 'collapsar' model.
authors.affiliation: Astronomical Observatory, NBIfAFG, University of Copenhagen, Juliane Maries Vej, DK-2100 Copenhagen Ø, Denmark. jens@astro.ku.dk
authors.forename: Jens
authors.initials: J
authors.lastname: Hjorth
authors.forename: Jesper
authors.initials: J
authors.lastname: Sollerman
authors.forename: Palle
authors.initials: P
authors.lastname: Møller
authors.forename: Johan P U
authors.initials: JP
authors.lastname: Fynbo
authors.forename: Stan E
authors.initials: SE
authors.lastname: Woosley
authors.forename: Chryssa
authors.initials: C
authors.lastname: Kouveliotou
authors.forename: Nial R
authors.initials: NR
authors.lastname: Tanvir
authors.forename: Jochen
authors.initials: J
authors.lastname: Greiner
authors.forename: Michael I
authors.initials: MI
authors.lastname: Andersen
authors.forename: Alberto J
authors.initials: AJ
authors.lastname: Castro-Tirado
authors.forename: José María
authors.initials: JM
authors.lastname: Castro Cerón
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Fruchter
authors.forename: Javier
authors.initials: J
authors.lastname: Gorosabel
authors.forename: Páll
authors.initials: P
authors.lastname: Jakobsson
authors.forename: Lex
authors.initials: L
authors.lastname: Kaper
authors.forename: Sylvio
authors.initials: S
authors.lastname: Klose
authors.forename: Nicola
authors.initials: N
authors.lastname: Masetti
authors.forename: Holger
authors.initials: H
authors.lastname: Pedersen
authors.forename: Kristian
authors.initials: K
authors.lastname: Pedersen
authors.forename: Elena
authors.initials: E
authors.lastname: Pian
authors.forename: Eliana
authors.initials: E
authors.lastname: Palazzi
authors.forename: James E
authors.initials: JE
authors.lastname: Rhoads
authors.forename: Evert
authors.initials: E
authors.lastname: Rol
authors.forename: Edward P J
authors.initials: EP
authors.lastname: van den Heuvel
authors.forename: Paul M
authors.initials: PM
authors.lastname: Vreeswijk
authors.forename: Darach
authors.initials: D
authors.lastname: Watson
authors.forename: Ralph A M J
authors.initials: RA
authors.lastname: Wijers