title: Explosive lithium production in the classical nova V339 Del (Nova Delphini 2013).
abstract: The origin of lithium (Li) and its production process have long been uncertain. Li could be produced by Big Bang nucleosynthesis, interactions of energetic cosmic rays with interstellar matter, evolved low-mass stars, novae, and supernova explosions. Chemical evolution models and observed stellar Li abundances suggest that at least half the Li may have been produced in red giants, asymptotic giant branch (AGB) stars, and novae. No direct evidence, however, for the supply of Li from evolved stellar objects to the Galactic medium has hitherto been found. Here we report the detection of highly blue-shifted resonance lines of the singly ionized radioactive isotope of beryllium, (7)Be, in the near-ultraviolet spectra of the classical nova V339 Del (Nova Delphini 2013) 38 to 48 days after the explosion. (7)Be decays to form (7)Li within a short time (half-life of 53.22 days). The (7)Be was created during the nova explosion via the alpha-capture reaction (3)He(α,γ)(7)Be (ref. 5). This result supports the theoretical prediction that a significant amount of (7)Li is produced in classical nova explosions.
authors.affiliation: Subaru Telescope, National Astronomical Observatory of Japan, 650 North A'ohoku Place, Hilo, Hawaii 96720, USA.
authors.forename: Akito
authors.initials: A
authors.lastname: Tajitsu
authors.affiliation: Astronomical Institute, Osaka Kyoiku University, Asahigaoka, Kashiwara, Osaka 582-8582, Japan.
authors.forename: Kozo
authors.initials: K
authors.lastname: Sadakane
authors.affiliation: 1] Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan [2] Nayoro Observatory, 157-1 Nisshin, Nayoro, Hokkaido 096-0066, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Naito
authors.affiliation: 1] Center for Astronomy, University of Hyogo, Sayo-cho, Hyogo 679-5313, Japan [2] Koyama Astronomical Observatory, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto 603-8555, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Arai
authors.affiliation: National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan.
authors.forename: Wako
authors.initials: W
authors.lastname: Aoki