@inproceedings{d45e75d8667f4097aa832e0032f0f681,
title = "Fluorine in the carbon-enhanced metal-poor star HE 1305+0132",
abstract = "The fluorine abundance of the Carbon-Enhanced Metal-Poor (CEMP) star HE 1305+0132 has been derived by analysis of the molecular HF (1-0) R9 line at 2.3357 μm in a high-resolution (R=50,000) spectrum obtained with the Phoenix spectrometer and Gemini-South telescope. Our abundance analysis makes use of a CNO-enhanced ATLAS12 model atmosphere characterized by a metallicity and CNO enhancements determined utilizing medium-resolution (R=3,000) optical and near-IR spectra. The effective iron abundance is found to be [Fe/H]=-2.5, making HE 1305+0132 the most Fe-deficient star, by more than an order of magnitude, for which the abundance of fluorine has been measured. Using spectral synthesis, we derive a super-solar fluorine abundance of A(19F)=4.96±0. 21, corresponding to a relative abundance of [F/Fe]=+2.90. A single line of the Phillips C2 system is identified in our Phoenix spectrum, and along with multiple lines of the first-overtone vibration-rotation CO (3-1) band head, C and O abundances of A(12C)=8.57±0.11 and A( 16O)=7.04±0.14 are derived. We consider the striking fluorine overabundance in the framework of the nucleosynthetic processes thought to be responsible for the C-enhancement of CEMP stars and conclude that the atmosphere of HE 1305+0132 was polluted via mass transfer by a primary companion during its asymptotic giant branch phase. This is the first study of fluorine in a CEMP star, and it demonstrates that this rare nuclide can be a key diagnostic of nucleosynthetic processes in the early Galaxy.",
keywords = "Abundances, Pop II Stars",
author = "Schuler, {Simon C.} and Katia Cunha and Smith, {Verne V.} and Thirupathi Sivarani and Beers, {Timothy C.} and Lee, {Young Sun}",
year = "2008",
doi = "10.1063/1.2905539",
language = "English (US)",
isbn = "9780735405097",
series = "AIP Conference Proceedings",
pages = "192--196",
booktitle = "First Stars III",
note = "First Stars III ; Conference date: 15-07-2007 Through 20-07-2007",
}