相关论文: Fluorine Abundances in the Orion Nebula Cluster
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…
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…
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…
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…
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…
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…
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…
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…
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…
Oxygen abundances are derived in a sample of 13 field F and G dwarfs and subgiants with metallicities in the range of -0.75 < [Fe/H] < +0.15. This is the same sample of stars for which boron abundances have been derived earlier from…
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…
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…
We present a new determination of the solar fluorine abundance together with abundance measurements of fluorine in two Galactic open clusters. We analyzed a sunspot spectrum, observed by L. Wallace and W. Livingston with the FTS at the…
With abundances and 2{\sigma} upper limits of fluorine (F) in seven metal-poor field giants, nucleosynthesis of stellar F at low metallicity is discussed. The measurements are derived from the HF(1-0) R9 line at 23358{\AA} using…
We present fluorine abundances in seven red-giant members of the globular cluster M4 (NGC 6121). These abundances were derived from the HF (1--0) R9 line at 2.3357 microns in high-resolution infrared spectra obtained with the Phoenix…
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…
Revised spectroscopic parameters for the HF molecule and a new CN line list in the 2.3 mu region have been recently available, allowing a revision of the F content in AGB stars. AGB carbon stars are the only observationally confirmed…
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…
We present the result of a systematic search for the iron Kalpha fluorescent line at 6.4 keV among 1616 X-ray sources detected by ultra-deep Chandra observations of the Orion Nebula Cluster and the obscured Orion Molecular Cloud 1…
First results from a study into the abundance trends of oxygen in the Galactic thin and thick disks are presented. Oxygen abundances for 63 nearby F and G dwarf stars, based on very high resolution spectra ($R\sim215 000$) and high…