Related papers: Molecular fluorine chemistry in the early Universe
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…
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…
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…
At early times the Universe was filled up with an extremely dense and hot gas. Due to the expansion it cooled below the binding energies of atoms which led to the formation of the first nuclei. In the physical environment of the…
Primordial molecules were formed during the Dark Ages, i.e. the time between recombination and reionization in the early Universe. The purpose of this article is to analyze the formation of primordial molecules based on heavy elements…
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…
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…
We present a theoretical investigation of the chemistry of fluorine-bearing molecules in diffuse and dense interstellar gas clouds. The chemistry of interstellar fluorine is qualitatively different from that of any other element, because -…
Chemistry plays a particular role in astrophysics. After atomic hydrogen, helium and their ions, the Universe probably contains more mass in molecules than in any other species. Molecule formation in the early, pre-galactic Universe may…
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,…
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…
Although they are only minor constituents of the interstellar medium, halogen-containing molecules are of special interest because of their unique thermochemistry. Here, we present a theoretical study of the chemistry of interstellar…
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…
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…
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…
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…
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…
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 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…
For a brief time in its early evolution the Universe was a cosmic nuclear reactor. The expansion and cooling of the Universe limited this epoch to the first few minutes, allowing time for the synthesis in astrophysically interesting…