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Related papers: Fluorine abundances in planetary nebulae

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Neutral fluorine (F I) lines are identified in the optical spectra of cool EHe stars. These are the first identification of F I lines in a star's spectrum, and provide the first measurement of fluorine abundances in EHe stars. The results…

Astrophysics · Physics 2011-02-11 Gajendra Pandey

We present measurements of the fluorine abundance in a Galactic Bulge Asymptotic Giant Branch (AGB) star. The measurements were performed using high resolution K-band spectra obtained with the CRIRES spectrograph, which has been recently…

We have discovered lines of highly ionized fluorine (Fv and Fvi) in the far-UV spectra of extremely hot (Teff=85,000--150,000 K) post-AGB stars. Our sample comprises H-rich central stars of planetary nebulae as well as H-deficient PG1159…

Astrophysics · Physics 2007-05-23 K. Werner , T. Rauch , J. W. Kruk

Fluorine is one of the most interesting elements for nuclear and stellar astrophysics. Fluorine abundance was first measured for stars other than the Sun in 1992, then for a handful metal-poor stars, which are likely to have formed in the…

An analysis of the fluorine abundance in Galactic AGB carbon stars (24 N-type, 5 SC-type and 5 J-type) is presented. This study uses the state- of-the-art carbon rich atmosphere models and improved atomic and molecular line lists in the 2.3…

We have found the fluorine lines [F IV] 3996.92A,4059.90A in the extremely metal-poor ([Ar/H] = -2.10+/-0.21) halo planetary nebula (PN) BoBn 1 in high-dispersion spectra from the 8.2-m VLT/UVES archive. Chemical abundance analysis shows…

Astrophysics · Physics 2009-11-13 Masaaki Otsuka , Hideyuki Izumiura , Akito Tajitsu , Siek Hyung

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…

Astrophysics of Galaxies · Physics 2015-06-03 A. Recio-Blanco , P. de Laverny , C. Worley , N. C. Santos , C. Melo , G. Israelian

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…

Solar and Stellar Astrophysics · Physics 2015-08-19 Catherine A. Pilachowski , Cameron Pace

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…

Astrophysics · Physics 2009-11-07 K. Cunha , V. V. Smith , D. L. Lambert , K. H. Hinkle

The origin of 'cosmic' fluorine is uncertain, but there are three proposed production sites/mechanisms: AGB stars, $\nu$ nucleosynthesis in Type II supernovae, and/or the winds of Wolf-Rayet stars. The relative importance of these…

Astrophysics of Galaxies · Physics 2015-06-22 H. Jönsson , N. Ryde , G. M. Harper , M. J. Richter , K. H. Hinkle

Asymptotic Giant Branch stars are known to produce `cosmic' fluorine but it is uncertain whether these stars are the main producers of fluorine in the Solar neighborhood or if any of the other proposed formation sites, type II supernovae…

Solar and Stellar Astrophysics · Physics 2017-01-25 H. Jönsson , N. Ryde , E. Spitoni , F. Matteucci , K. Cunha , V. Smith , K. Hinkle , M. Schultheis

Neutral fluorine (F I) lines are identified in the optical spectra of several R Coronae Borealis stars (RCBs) at maximum light. These lines provide the first measurement of the fluorine abundance in these stars. Fluorine is enriched in some…

Astrophysics · Physics 2009-11-13 Gajendra Pandey , David L. Lambert , N. Kameswara Rao

Fluorine (19F) abundances are derived in a sample of 6 bulge red giants in Baade's Window. These giants span a factor of 10 in metallicity and this is the first study to define the behavior of 19F with metallicity in the bulge. The bulge…

Astrophysics · Physics 2009-11-13 K. Cunha , V. V. Smith , B. K. Gibson

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…

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…

Neutral fluorine lines are identified in the optical spectra of several R Coronae Borealis stars (RCBs) at maximum light. These lines provide the first measurement of the fluorine abundance in these stars. Fluorine is enriched in some RCBs…

Astrophysics · Physics 2007-12-27 Gajendra Pandey , David L. Lambert , N. Kameswara Rao

The main objective of this paper is to explore abundances of fluorine in hot Extreme Helium Stars (EHes). Overabundance of fluorine is a characteristic feature for cool EHes and R Coronae Borealis (RCB) stars and further enforces their…

Solar and Stellar Astrophysics · Physics 2020-03-11 Anirban Bhowmick , Gajendra Pandey , David L. Lambert

A reanalysis of the fluorine abundance in three Galactic AGB carbon stars (TX Psc, AQ Sgr and R Scl) has been performed from the molecular HF (1-0) R9 line at 2.3358 $\mu$m. High-resolution (R$\sim 50000$) and high signal to noise spectra…

Astrophysics · Physics 2011-02-11 C. Abia , A. Recio-Blanco , P. de Laverny , S. Cristallo , I. Dominguez , O. Straniero

Fluorine (19F) abundances (or upper limits) are derived in six extragalactic AGB carbon stars from the HF(1-0) R9 line at 2.3358 mu in high resolution spectra. The stars belong to the Local Group galaxies LMC, SMC and Carina dwarf…

Solar and Stellar Astrophysics · Physics 2015-05-28 C. Abia , K. Cunha , S. Cristallo , P. de Laverny , I. Domínguez , A. Recio-Blanco , V. V. Smith , O. Straniero

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,…

Astrophysics of Galaxies · Physics 2019-10-23 Keith A. Olive , Elisabeth Vangioni
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