English
Related papers

Related papers: Halo Star Lithium Depletion

200 papers

We find that hot jupiter host stars within the T$_\mathrm{eff}$ range 5900-6300K show lower Li abundances, by 0.14 dex, than stars without detected planets. This offset has a significance at the level 7$\sigma$, pointing to a stronger…

The current status of observational studies of lithium depletion in open clusters is reviewed, concentrating mainly on G and K type stars. I attempt to answer the following questions: Can the lithium depletion patterns seen in open clusters…

Astrophysics · Physics 2007-05-23 R. D. Jeffries

Un-evolved, very metal-poor stars are the most important tracers of the cosmic abundance of lithium in the early universe. Combining the standard Big Bang nucleosynthesis model with Galactic production through cosmic ray spallation, these…

Solar and Stellar Astrophysics · Physics 2015-06-16 Karin Lind , Jorge Melendez , Martin Asplund , Remo Collet , Zazralt Magic

The evolution of the 7Li abundance in the Galaxy has been computed by taking into account several 7Li sources: novae, massive AGB stars, C-stars, Type II SNe and GCRs. The theoretical predictions for the evolution of the 7Li abundance in…

Astrophysics · Physics 2011-05-23 D. Romano , F. Matteucci , P. Molaro , P. Bonifacio

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

Israelian et al. (2004) reported that exoplanet host stars are lithium depleted compared to solar-type stars without detected massive planets, a result recently confirmed by Gonzalez (2008). We investigate whether enhanced lithium depletion…

Astrophysics · Physics 2009-11-13 Jerome Bouvier

Lithium is an excellent tracer of mixing in stars as it is destroyed (by nuclear reactions) at a temperature around $\sim 2.5\times 10^6$ K. The lithium destruction zone is typically located in the radiative region of a star. If the…

Astrophysics · Physics 2007-05-23 Brian Chaboyer

I review basic observational features in Population I stars which strongly implicate rotation as a mixing agent; these include dispersion at fixed temperature in coeval populations and main sequence lithium depletion for a range of masses…

Solar and Stellar Astrophysics · Physics 2015-05-18 M. H. Pinsonneault

We compute rotating 1D stellar evolution models that include a modified temperature gradient in convection zones and criterion for convective instability inspired by rotating 3D hydrodynamical simulations performed with the MUSIC code. In…

Solar and Stellar Astrophysics · Physics 2021-10-27 Thomas Constantino , Isabelle Baraffe , Thomas Goffrey , Jane Pratt , Thomas Guillet , Dimitar Vlaykov , Louis Amard

The lithium abundance in 62 halo dwarfs is determined from accurate equivalent widths reported in the literature and an improved infrared flux method (IRFM) temperature scale. The Li abundance of 41 plateau stars (those with Teff > 6000 K)…

Astrophysics · Physics 2009-11-10 Jorge Melendez , Ivan Ramirez

The lithium abundance in turnoff stars of the old population of our Galaxy is remarkably constant in the metallicity interval -2.8\textless{}[Fe/H] \textless{}-2.0, defining a plateau. The Li abundance of these turnoff stars is clearly…

Astrophysics of Galaxies · Physics 2015-10-21 Monique Spite , François Spite , Elisabetta Caffau , Piercarlo Bonifacio

The observed amount of lithium for low metallicity population II stars (known as the Spite plateau) is a factor of $\sim 3-5$ lower than the predictions of the standard cosmology. Since the observations are limited to the local Universe…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-06 Maxim Pospelov , Niayesh Afshordi

Transport processes occurring in the radiative interior of solar-type stars are evidenced by the surface variation of light elements, in particular Li, and the evolution of their rotation rates. For the Sun, inversions of helioseismic data…

Solar and Stellar Astrophysics · Physics 2021-02-10 T. Dumont , A. Palacios , C. Charbonnel , O. Richard , L. Amard , K. Augustson , S. Mathis

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

We aim to constrain the mixing processes in low-mass stars by investigating the behaviour of the Li surface abundance after the main sequence. We take advantage of the data from the sixth internal data release of Gaia-ESO, idr6, and from…

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

In this review I briefly discuss the theory of pre-main-sequence (PMS) Li depletion in low-mass (0.075<M<1.2 Msun) stars and highlight those uncertain parameters which lead to substantial differences in model predictions. I then summarise…

Astrophysics · Physics 2015-12-09 R. D. Jeffries

We examine outstanding issues in the analysis and interpretation of the halo Li plateau. We show that the majority of very Li-poor halo Li-plateau stars (5 out of 8) have high projected rotation velocities vsini between 4.7 and 10.4 km…

Astrophysics · Physics 2007-05-23 Sean G. Ryan , Lisa Elliott

Lithium abundances are presented for a sample of 181 nearby F and G dwarfs with accurate {\it Hipparcos} parallaxes. The stars are on circular orbits about the Galactic centre and, hence, are identified as belonging to the thin disk. This…

Astrophysics · Physics 2009-11-10 David L. Lambert , Bacham E. Reddy

Despite the extensive study of lithium depletion during pre-main-sequence contraction, studies of individual stars show discrepancies between ages determined from the HR diagram and ages determined from lithium depletion (Song et al. 2002,…

Solar and Stellar Astrophysics · Physics 2015-05-18 Jennifer C. Yee , Eric L. N. Jensen