title: Early solar system. Stellar origin of the ¹⁸²Hf cosmochronometer and the presolar history of solar system matter.
abstract: Among the short-lived radioactive nuclei inferred to be present in the early solar system via meteoritic analyses, there are several heavier than iron whose stellar origin has been poorly understood. In particular, the abundances inferred for (182)Hf (half-life = 8.9 million years) and (129)I (half-life = 15.7 million years) are in disagreement with each other if both nuclei are produced by the rapid neutron-capture process. Here, we demonstrate that contrary to previous assumption, the slow neutron-capture process in asymptotic giant branch stars produces (182)Hf. This has allowed us to date the last rapid and slow neutron-capture events that contaminated the solar system material at ~100 million years and ~30 million years, respectively, before the formation of the Sun.
authors.affiliation: Monash Centre for Astrophysics (MoCA), Monash University, Clayton VIC 3800, Australia. maria.lugaro@monash.edu.
authors.forename: Maria
authors.initials: M
authors.lastname: Lugaro
authors.affiliation: Monash Centre for Astrophysics (MoCA), Monash University, Clayton VIC 3800, Australia. Joint Institute for Nuclear Astrophysics (JINA), 225 Nieuwland Science Hall, Department of Physics, University of Notre Dame, Notre Dame, IN 46556-5670, USA. School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Heger
authors.affiliation: Monash Centre for Astrophysics (MoCA), Monash University, Clayton VIC 3800, Australia.
authors.forename: Dean
authors.initials: D
authors.lastname: Osrin
authors.affiliation: Institut d'Astronomie et d'Astrophysique, Université Libre de Bruxelles, CP-226, 1050, Brussels, Belgium.
authors.forename: Stephane
authors.initials: S
authors.lastname: Goriely
authors.affiliation: Institut für Kern- und Teilchenphysik, Technische Universität Dresden, 01069 Dresden, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Zuber
authors.affiliation: Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611, Australia. Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, the University of Tokyo, Japan.
authors.forename: Amanda I
authors.initials: AI
authors.lastname: Karakas
authors.affiliation: Jeremiah Horrocks Institute, University of Central Lancashire, Preston, PR1 2HE, UK. Institute for Computational Astrophysics, Department of Astronomy and Physics, Saint Mary's University, Halifax, NS, BH3 3C3, Canada. UK Network for Bridging Disciplines of Galactic Chemical Evolution (BRIDGCE), www.astro.keele.ac.uk/bridgce, UK.
authors.forename: Brad K
authors.initials: BK
authors.lastname: Gibson
authors.affiliation: Monash Centre for Astrophysics (MoCA), Monash University, Clayton VIC 3800, Australia.
authors.forename: Carolyn L
authors.initials: CL
authors.lastname: Doherty
authors.affiliation: Monash Centre for Astrophysics (MoCA), Monash University, Clayton VIC 3800, Australia.
authors.forename: John C
authors.initials: JC
authors.lastname: Lattanzio
authors.affiliation: Faculty of Natural Science, University of West Hungary, 9700 Szombathely, Hungary.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Ott