NOAO >   Observing Info >   Approved Programs >   2015A-0095

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Program Information for 2015A-0095


PI: Henrik Jonsson, Lund Observatory, henrikj@astro.lu.se
Address: Department of Astronomy and Theoretical Physics, Box 43, Lund SE-221 00 Sweden

CoI: Nils Ryde, Lund Observatory
CoI: Kenneth H Hinkle, NOAO
CoI: Francesca Matteucci, Osservatorio Astronomico di Trieste
CoI: Valentina Grieco, Osservatorio Astronomico di Trieste
CoI: Katia Cunha, Observatorio Nacional Brazil
CoI: Patrick De Laverny, Observatoire de la Cote d'Azur
CoI: Alejandra Recio-Blanco, Observatoire de la Cote d'Azur
CoI: Mathias Schultheis, Observatoire de la Cote d'Azur
CoI: Verne V Smith, NOAO

Title: The origin of fluorine in the Solar neighborhood: the possible contribution by Wolf-Rayet stars

Abstract: The cosmic origin of fluorine is, amazingly enough, still not well established. Production of fluorine in AGB stars has been observationally proven but it is uncertain whether the amount of fluorine produced can explain the cosmic abundance. Over the years, there have been claims both for and against AGB stars being the dominant fluorine producer in the Galaxy. Other proposed production sites are Wolf-Rayet stars and supernovae Type II via the $\nu$-process. The molecular data of the HF molecule, that is used for fluorine abundance determination, has recently been re-evaluated and revised by us \cite{2014AnA...564A.122J} leading to, in several cases, a downward correction of $\sim$0.3 dex of the fluorine abundances. In a recent ApJ {\it Letters} \cite{2014ApJ...789L..41J}, we draw the conclusion that the cosmic fluorine in the solar neighborhood was probably dominated by the production in AGB stars, but this is based on a small number of stars with a small range of metallicity. To probe the possible contribution of Wolf-Rayet stars to the cosmic fluorine abundance, we hereby propose observations of more metal-rich stars, for which the possible Wolf-Rayet signature should be large.

Program Type: Standard/Galactic

Scheduled Nights:
Run 1 (2015A):  KP-4m/PHNX -- 4n on May 29 - Jun 01 2015


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NOAO >   Observing Info >   Approved Programs >   2015A-0095

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