相关论文: The ramp-up of interstellar medium enrichment at z…
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…
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,…
Wolf-Rayet (WR) stars have recently attracted attention as possible drivers of early chemical enrichment, including the production of fluorine, whose nucleosynthetic origin remains debated. To test the contribution of massive stars to…
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…
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…
Fluorine has many different potential sites and channels of production, making narrowing down a dominant site of fluorine production particularly challenging. In this work, we investigate which sources are the dominant contributors to the…
We have determined fluorine abundances from the F II 4789 and F IV 4060 nebular emission lines for a sample of planetary nebulae (PNe). Our results show that fluorine is generally overabundant in PNe, thus providing new evidence for the…
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…
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…
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…
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 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.…
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…
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…
Some models of Big Bang nucleosynthesis suggest that very high baryon density regions were formed in the early Universe, and generated the production of heavy elements other than lithium such as fluorine F. We present a comprehensive…
The main astrophysical factories of fluorine (19F) are thought to be Type II supernovae, Wolf-Rayet stars, and the asymptotic giant branch (AGB) of intermediate mass stars. We present a model for the chemical evolution of fluorine in the…
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…
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…
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…
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…