title: A single low-energy, iron-poor supernova as the source of metals in the star SMSS J031300.36-670839.3.
abstract: The element abundance ratios of four low-mass stars with extremely low metallicities (abundances of elements heavier than helium) indicate that the gas out of which the stars formed was enriched in each case by at most a few--and potentially only one--low-energy supernova. Such supernovae yield large quantities of light elements such as carbon but very little iron. The dominance of low-energy supernovae seems surprising, because it had been expected that the first stars were extremely massive, and that they disintegrated in pair-instability explosions that would rapidly enrich galaxies in iron. What has remained unclear is the yield of iron from the first supernovae, because hitherto no star has been unambiguously interpreted as encapsulating the yield of a single supernova. Here we report the optical spectrum of SMSS J031300.36-670839.3, which shows no evidence of iron (with an upper limit of 10(-7.1) times solar abundance). Based on a comparison of its abundance pattern with those of models, we conclude that the star was seeded with material from a single supernova with an original mass about 60 times that of the Sun (and that the supernova left behind a black hole). Taken together with the four previously mentioned low-metallicity stars, we conclude that low-energy supernovae were common in the early Universe, and that such supernovae yielded light-element enrichment with insignificant iron. Reduced stellar feedback both chemically and mechanically from low-energy supernovae would have enabled first-generation stars to form over an extended period. We speculate that such stars may perhaps have had an important role in the epoch of cosmic reionization and the chemical evolution of early galaxies.
authors: Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia.
authors: S C
authors: SC
authors: Keller
authors: Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia.
authors: M S
authors: MS
authors: Bessell
authors: Department of Physics, Massachusetts Institute of Technology and Kavli Institute for Astrophysics and Space Research, Cambridge, Massachusetts 02139, USA.
authors: A
authors: A
authors: Frebel
authors: Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia.
authors: A R
authors: AR
authors: Casey
authors: Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia.
authors: M
authors: M
authors: Asplund
authors: Department of Physics, Massachusetts Institute of Technology and Kavli Institute for Astrophysics and Space Research, Cambridge, Massachusetts 02139, USA.
authors: H R
authors: HR
authors: Jacobson
authors: Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
authors: K
authors: K
authors: Lind
authors: Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia.
authors: J E
authors: JE
authors: Norris
authors: Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia.
authors: D
authors: D
authors: Yong
authors: School of Mathematical Sciences, Monash University, Victoria 3800, Australia.
authors: A
authors: A
authors: Heger
authors: 1] Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia [2] Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Strasse 1, Garching 85741, Germany.
authors: Z
authors: Z
authors: Magic
authors: Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia.
authors: G S
authors: GS
authors: Da Costa
authors: Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia.
authors: B P
authors: BP
authors: Schmidt
authors: Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston, Australian Capital Territory 2611, Australia.
authors: P
authors: P
authors: Tisserand