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Related papers: The Interstellar $^7$Li/$^6$Li Ratio

200 papers

Lithium is extensively known to be a good tracer of non-standard mixing processes occurring in stellar interiors. We present the results of a new large Lithium survey in red giant stars and combine it with surveys from the literature to…

Solar and Stellar Astrophysics · Physics 2020-01-08 C. Charbonnel , N. Lagarde , G. Jasniewicz , P. North , M. Shetrone , J. Krugler Hollek , V. V. Smith , R. Smiljanic , A. Palacios , G. Ottoni

The nuclei of the lithium isotopes are fragile, easily destroyed, so that, at variance with most of the other elements, they cannot be formed in stars through steady hydrostatic nucleosynthesis. The 7Li isotope is synthesized during…

Astrophysics of Galaxies · Physics 2015-05-18 Monique Spite , François Spite

Thirty years after the first observation of the 7Li isotope in the atmosphere of metal-poor halo stars, the puzzle about its origin persists. Do current observations still support the existence of a "plateau": a single value of lithium…

Astrophysics of Galaxies · Physics 2012-07-10 Fabio Iocco

Lithium abundances have been determined in more than 100 metal-poor halo stars both in the field and in clusters. From these data we find trends of Li with both temperature and metallicity and a real dispersion in Li abundances in the Spite…

Astrophysics · Physics 2009-11-11 Ann Merchant Boesgaard , Megan C. Novicki , Alex Stephens

The lithium abundances for 378 G/K giants are derived with non-LTE correction considered. Among these, there are 23 stars that host planetary systems. The lithium abundance is investigated, as a function of metallicity, effective…

Solar and Stellar Astrophysics · Physics 2015-06-19 Y. J. Liu , K. F. Tan , L. Wang , G. Zhao , Bun'ei Sato , Y. Takeda , H. N. Li

Current measurements indicate that the deuterium abundance in diffuse interstellar gas varies spatially by a factor of ~4 among sightlines extending beyond the Local Bubble. One plausible explanation for the scatter is the variable…

Astrophysics · Physics 2009-11-10 Jason X. Prochaska , Todd M. Tripp , J. Christopher Howk

I consider the synthesis of 6Li due to the decay of relic particles, such as gravitinos or moduli, after the epoch of Big Bang Nucleosynthesis. The synthesized 6Li/H ratio may be compared to 6Li/H in metal-poor stars which, in the absence…

Astrophysics · Physics 2009-10-31 K. Jedamzik

Preliminary abundances of lithium and a few other elements have been obtained for 31 field Am stars with good Hipparcos parallaxes, as well as for 36 normal A and F stars. Radial and projected rotational velocities were determined as well.…

Astrophysics · Physics 2009-11-11 P. North , F. Betrix , C. Besson

Using very high-resolution (R$\sim$ 125,000) and high quality (S/N $\geq$ 350) spectra, we have searched for $^{6}$Li in stars hosting extra-solar planets. From detailed profile-fitting of the Li {\sc i} resonance line at 6707.7 \AA, we…

Astrophysics · Physics 2009-11-07 Bacham E. Reddy , David L. Lambert , Chris Laws , Guillermo Gonzalez , Kevin Covey

Isotopic ratios of heavy elements are a key signature of the nucleosynthesis processes in stellar interiors. The contribution of successive generations of stars to the metal enrichment of the Universe is imprinted on the evolution of…

Astrophysics of Galaxies · Physics 2016-11-09 S. H. J. Wallstrom , S. Muller , M. Guelin

This work presents a homogeneous determination of lithium abundances in a large sample of giant-planet hosting stars (N=117), and a control sample of disk stars without detected planets (N=145). The lithium abundances were derived using a…

Solar and Stellar Astrophysics · Physics 2010-11-04 L. Ghezzi , K. Cunha , V. V. Smith , R. de la Reza

The work functions of 7Li and 6Li metals have been measured as a function of temperature, by using photoionization of pure isolated metal nanoparticles in a beam. These data reveal a marked isotope effect in the temperature variation of…

Mesoscale and Nanoscale Physics · Physics 2026-02-18 Atef A. Sheekhoon , Abdelrahman O. Haridy , Vitaly V. Kresin

A large number of stellar evolution models with [Fe/H] = -2.3 and -3.3 have been calculated in order to determine the primordial $^7$Li abundance and to test current stellar evolution models by a comparison to the extensive database of Li…

Astrophysics · Physics 2009-10-22 Brian Chaboyer , P. Demarque

Bound state properties of the four-electron lithium ion Li$^{-}$ in its ground $2^{2}S-$state and isotope-subsistuted ${}^{6}$Li$^{-}$ and ${}^{7}$Li$^{-}$ ions in their ground $2^1S-$state(s) are determined from the results of accurate,…

Atomic Physics · Physics 2015-07-16 Alexei M. Frolov , David M. Wardlaw

The chemical evolution of lithium in the Milky Way represents a major problem in modern astrophysics. Indeed, lithium is, on the one hand, easily destroyed in stellar interiors, and, on the other hand, produced at some specific stellar…

Astrophysics of Galaxies · Physics 2016-10-26 G. Guiglion , P. de Laverny , A. Recio-Blanco , C. C. Worley , M. De Pascale , T. Masseron , N. Prantzos , S. Mikolaitis

Interstellar objects provide a unique opportunity to further our understanding of the planetary formation process by studying in detail material formed around another star. Their ices contain precious clues about the environment and…

We calculate and discuss the chemical evolution of the isotopic silicon abundances in the interstellar medium at distances and times appropriate to the birth of the solar system. This has several objectives, some of which are related to…

Astrophysics · Physics 2009-10-28 F. X. Timmes , Donald D. Clayton

Recent detection of the isotope $^7$Be (that decays into $^7$Li) in the outburst of classical novae confirms the suggestion made in the 70s that novae could make $^7$Li. We reconsidered the role of novae as producers of Li by means of a…

Solar and Stellar Astrophysics · Physics 2019-01-16 Gabriele Cescutti , Paolo Molaro

The WMAP determination of the baryon-to-photon ratio implies, through Big Bang nucleosynthesis, a cosmological Li abundance larger, by a factor of 2 to 3, than the Li abundance plateau observed in the oldest Pop II stars. It is however…

Astrophysics · Physics 2009-11-10 Olivier Richard , Georges Michaud , Jacques Richer

While theoretical computations of the lithium abundances in Pop II stars predict variations from star to star, the most recent observations confirm the existence of a "lithium plateau" with no abundance dispersion. This apparent paradox has…

Astrophysics · Physics 2007-05-23 Sylvie Vauclair