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相关论文: Fluorine Abundances of Galactic Low-Metallicity Gi…

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The chemical evolution of fluorine is investigated in a sample of Milky Way red giantstars that span a significant range in metallicity from [Fe/H] $\sim$ -1.3 to 0.0 dex. Fluorine abundances are derived from vibration-rotation lines of HF…

太阳与恒星天体物理 · 物理学 2019-11-11 Rafael Guerço , Katia Cunha , Verne V. Smith , Christian R. Hayes , Carlos Abia , David L. Lambert , Henrik Jönsson , Nils Ryde

The cosmic origin of fluorine is still not well constrained. Several nucleosynthetic channels at different phases of stellar evolution have been suggested, but these must be constrained by observations. For this, the fluorine abundance…

The chemical evolution of fluorine is still a matter of debate in Galactic archaeology, especially at low metallicities, where it is particularly challenging to obtain the corresponding chemical abundances from observations. We present here…

星系天体物理 · 物理学 2025-11-03 Valeria Grisoni , Federico Rizzuti , Gabriele Cescutti

We present the first fluorine measurements in 12 normal giants belonging to the Galactic thin and thick disks using spectra obtained with the Phoenix infrared spectrometer on the 2.1m telescope at Kitt Peak. Abundances are determined from…

星系天体物理 · 物理学 2024-06-06 K. E. Brady , C. A. Pilachowski , V. Grisoni , Z. G. Maas , K. A. Nault

In spite of many observational efforts aiming to characterize the chemical evolution of our Galaxy, not much is known about the origin of fluorine (F). Models suggest that the F found in the Galaxy might have been produced mainly in three…

星系天体物理 · 物理学 2015-06-03 A. Recio-Blanco , P. de Laverny , C. Worley , N. C. Santos , C. Melo , G. Israelian

The behavior of fluorine with metallicity has not yet been probed in any stellar population. In this work, we present the first fluorine abundances measured outside of the Milky Way from a sample of red giants in the Large Magellanic Cloud…

天体物理学 · 物理学 2009-11-07 K. Cunha , V. V. Smith , D. L. Lambert , K. H. Hinkle

Fluorine is massive enough that it is not considered to be a light ($Z\le5$) element, yet compared to its near neighbors, C, N, O, and Ne, it is far underproduced in the course of stellar evolution, making its origin more complex. In fact,…

星系天体物理 · 物理学 2019-10-23 Keith A. Olive , Elisabeth Vangioni

The abundance of fluorine is determined from the (2-0) R9 2.3358 micron feature of the molecule HF for several dozen normal G and K stars in the Galactic thin disk from spectra obtained with the Phoenix IR spectrometer on the 2.1-m…

太阳与恒星天体物理 · 物理学 2015-08-19 Catherine A. Pilachowski , Cameron Pace

Abundances of fluorine ($^{19}$F), as well as isotopic ratios of $^{16}$O/$^{17}$O, are derived in a sample of luminous young ($\sim$10$^{7}$--10$^{8}$ yrs) red giants in the Galactic center (with galactocentric distances ranging from…

The origin and evolution of fluorine in the Milky Way galaxy is still in debate. In particular, the increase of the [F/Fe] in metal-rich stars found from near-IR HF-lines is challenging to explain theoretically. We determine the fluorine…

星系天体物理 · 物理学 2023-08-09 G. Nandakumar , N. Ryde , G. Mace

We investigate the evolution of the abundance of fluorine in the Milky Way thick and thin discs by means of detailed chemical evolution models compared with recent observational data. The chemical evolution models adopted here have already…

星系天体物理 · 物理学 2020-08-19 Valeria Grisoni , Donatella Romano , Emanuele Spitoni , Francesca Matteucci , Nils Ryde , Henrik Jönsson

Possible main formation sites of F in the Universe include AGB stars, the {\nu}-process in Type II SNe, and/or W-R stars. The importance of the W-R stars has theoretically been questioned and they are probably not needed in the modelling of…

星系天体物理 · 物理学 2014-05-08 H. Jönsson , N. Ryde , G. M. Harper , K. Cunha , M. Schultheis , K. Eriksson , C. Kobayashi , V. V. Smith , M. Zoccali

We present an abundance analysis based on high resolution spectra of 8 stars selected to span the full range in metallicity in the Draco dwarf spheroidal galaxy. We find [Fe/H] for the sample stars ranges from -1.5 to -3.0 dex. Combining…

星系天体物理 · 物理学 2009-08-05 Judith G. Cohen , Wenjin Huang

I present a new Galactic chemical evolution model motivated by and grounded in the hierarchical theory of galaxy formation, as expressed by a halo merger history of the Galaxy. This model accurately reproduces the "metallicity distribution…

天体物理学 · 物理学 2009-11-13 Jason Tumlinson

Open clusters are ideal tools for tracing the abundances of different elements because their stars are expected to have the same age, distance, and metallicity. Therefore, they serve as very powerful tracers for investigating the cosmic…

In the last decade, the available measurements of fluorine abundance have increased significantly, providing additional information on the chemical evolution of our Galaxy and details on complex stellar nucleosynthesis processes. However,…

The origin of fluorine is still a debated question. AGB stars synthesise this element and likely contribute significantly to its synthesis in the present-day Universe. However, it is not clear whether other sources contribute, especially in…

Inhomogeneous chemical evolution models of galaxies which try to reproduce the scatter seen in element-to-iron ratios of metal-poor halo stars are heavily dependent on theoretical nucleosynthesis yields of core-collapse supernovae. Hence…

天体物理学 · 物理学 2009-11-06 D. Argast , M. Samland , F. -K. Thielemann , O. E. Gerhard

We present the N, O, F and Na abundance and 12C/13C isotopic ratio measurements or upper limits for a sample of 10 C-rich, metal-poor giant stars, eight enhanced in s-process (CEMP-s) elements and two poor in n-capture elements (CEMP-no).…

太阳与恒星天体物理 · 物理学 2015-05-20 Sara Lucatello , Thomas Masseron , Jennifer A. Johnson , Marco Pignatari , Falk Herwig

The source of fluorine is not well understood, although core-collapse supernovae, Wolf-Rayet stars, and asymptotic giant branch stars have been suggested. A search for evidence of the nu process during Type II supernovae is presented.…

天体物理学 · 物理学 2009-11-10 S. R. Federman , Yaron Sheffer , David L. Lambert , V. V. Smith
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