title: Origin of the p-process radionuclides 92Nb and 146Sm in the early solar system and inferences on the birth of the Sun.
abstract: The abundances of (92)Nb and (146)Sm in the early solar system are determined from meteoritic analysis, and their stellar production is attributed to the p process. We investigate if their origin from thermonuclear supernovae deriving from the explosion of white dwarfs with mass above the Chandrasekhar limit is in agreement with the abundance of (53)Mn, another radionuclide present in the early solar system and produced in the same events. A consistent solution for (92)Nb and (53)Mn cannot be found within the current uncertainties and requires the (92)Nb/(92)Mo ratio in the early solar system to be at least 50% lower than the current nominal value, which is outside its present error bars. A different solution is to invoke another production site for (92)Nb, which we find in the α-rich freezeout during core-collapse supernovae from massive stars. Whichever scenario we consider, we find that a relatively long time interval of at least ∼ 10 My must have elapsed from when the star-forming region where the Sun was born was isolated from the interstellar medium and the birth of the Sun. This is in agreement with results obtained from radionuclides heavier than iron produced by neutron captures and lends further support to the idea that the Sun was born in a massive star-forming region together with many thousands of stellar siblings.
authors.affiliation: Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, H-1121 Budapest, Hungary; Monash Centre for Astrophysics, Monash University, Clayton, VIC 3800, Australia; maria.lugaro@csfk.mta.hu.
authors.forename: Maria
authors.initials: M
authors.lastname: Lugaro
authors.affiliation: Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, H-1121 Budapest, Hungary; NuGrid Collaboration;
authors.forename: Marco
authors.initials: M
authors.lastname: Pignatari
authors.affiliation: Faculty of Natural Science, University of West Hungary, H-9700 Szombathely, Hungary; Max Planck Institute for Chemistry, D-55128 Mainz, Germany;
authors.forename: Ulrich
authors.initials: U
authors.lastname: Ott
authors.affiliation: Institut für Kern- und Teilchenphysik, Technische Universität Dresden, D-01069 Dresden, Germany;
authors.forename: Kai
authors.initials: K
authors.lastname: Zuber
authors.affiliation: NuGrid Collaboration; Osservatorio di Torino, I-10025 Pino Torinese, Italy;
authors.forename: Claudia
authors.initials: C
authors.lastname: Travaglio
authors.affiliation: Atomki Institute for Nuclear Research, Hungarian Academy of Sciences, H-4001 Debrecen, Hungary.
authors.forename: György
authors.initials: G
authors.lastname: Gyürky
authors.affiliation: Atomki Institute for Nuclear Research, Hungarian Academy of Sciences, H-4001 Debrecen, Hungary.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Fülöp
keywords: short-lived radionuclides; solar system formation; supernovae