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Related papers: The evolution of Lithium: implications of a univer…

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The conventional Big Bang model successfully anticipates the initial abundances of 2H(D), 3He, and 4He, aligning remarkably well with observational data. However, a persistent challenge arises in the case of 7Li, where the predicted…

Nuclear Theory · Physics 2024-04-25 C. A. Bertulani , Shubhchintak

A small fraction of red giants are known to be lithium (Li) rich, in contradiction with expectations from stellar evolutionary theory. A possible explanation for these atypical giants is the engulfment of a Li-rich planet or brown dwarf by…

Solar and Stellar Astrophysics · Physics 2016-10-05 Claudia Aguilera-Gómez , Julio Chanamé , Marc Pinsonneault , Joleen Carlberg

Thanks to the high multiplex and efficiency of Giraffe at the VLT we have been able for the first time to observe the Li I doublet in the Main Sequence (MS) stars of a Globular Cluster. At the same time we observed Li in a sample of…

Astrophysics of Galaxies · Physics 2015-05-14 J. I. González Hernández , P. Bonifacio , E. Caffau , M. Steffen , H. -G. Ludwig , N. Behara , L. Sbordone , R. Cayrel , S. Zaggia

We present data for four ultra-Li-deficient, warm, halo stars. The Li deficiency of two of these is a new discovery. Three of the four stars have effective temperatures Teff ~ 6300 K, in contrast to previously known Li-deficient halo stars…

Astrophysics · Physics 2009-10-31 Sean G. Ryan , Timothy C. Beers , Toshitaka Kajino , Katarina Rosolankova

Motivated by the recent report of a high Li6 ``plateau'' extending to low metallicities in Galactic halo stars, we study the energetics of an early production of Li6 through the interaction of energetic particles with the interstellar…

Astrophysics · Physics 2009-11-11 Nikos Prantzos

I shall review what has been learnt during 20 years of lithium observations in stars belonging to metal-poor globular clusters. The focus will be on little evolved main-sequence, turnoff-point (TOP) and subgiant-branch (SGB) stars expected…

Solar and Stellar Astrophysics · Physics 2012-06-28 A. J. Korn

Stars destroy lithium (Li) in their normal evolution. The convective envelopes of evolved red giants reach temperatures of millions of K, hot enough for the 7Li(p,alpha)4He reaction to burn Li efficiently. Only about 1% of first-ascent red…

Solar and Stellar Astrophysics · Physics 2012-05-31 Evan Kirby , Xiaoting Fu , Puragra Guhathakurta , Licai Deng

We investigate if there is a difference in the lithium abundances of stars belonging to two halo populations of F and G main-sequence stars previously found to differ in [alpha/Fe] for the metallicity range -1.4 < [Fe/H] < -0.7. Li…

Astrophysics of Galaxies · Physics 2015-06-05 P. E. Nissen , W. J. Schuster

The primordial abundances of light elements produced in the standard theory of Big Bang nucleosynthesis (BBN) depend only on the cosmic ratio of baryons to photons, a quantity inferred from observations of the microwave background. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 J. Christopher Howk , Nicolas Lehner , Brian D. Fields , Grant J. Mathews

We review three Li problems. First, the Li problem in the Sun, for which some previous studies have argued that it may be Li-poor compared to other Suns. Second, we discuss the Li problem in planet hosting stars, which are claimed to be…

Solar and Stellar Astrophysics · Physics 2010-11-22 J. Melendez , I. Ramirez , L. Casagrande , M. Asplund , B. Gustafsson , D. Yong , J. D. do Nascimento , M. Castro , M. Bazot

We present the non-local thermodynamic equilibrium (NLTE) abundances of up to 10 chemical species in a sample of 59 very metal-poor (VMP, -4 < [Fe/H] < -2) stars in seven dwarf spheroidal galaxies (dSphs) and in the Milky Way (MW) halo. Our…

Solar and Stellar Astrophysics · Physics 2017-12-27 L. Mashonkina , P. Jablonka , T. Sitnova , Yu. Pakhomov , P. North

This study investigates the temporal and spatial variations in lithium abundance within the Milky Way using a sample of 22,034 main-sequence turn-off (MSTO) stars and subgiants, characterised by precise stellar ages, 3D NLTE (non-local…

Astrophysics of Galaxies · Physics 2024-11-21 Tiancheng Sun , Shaolan Bi , Xunzhou Chen , Yuxi , Lu , Yuqin Chen , Ming-Yi Ding , Jianrong Shi , Hongliang Yan , Zhishuai Ge

We compare the properties of recent samples of the lithium abundances in halo stars to one another and to the predictions of theoretical models including rotational mixing, and we examine the data for trends with metal abundance. We find…

Astrophysics · Physics 2008-11-26 M. H. Pinsonneault , G. Steigman , T. P. Walker , V. K. Narayanan

To constrain the universe before recombination (380000 years after the Big Bang), we mostly rely on the measurements of the primordial abundances that indicate the first insight into the thermal history of the universe. The first production…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-30 Tahani Makki , Mounib El Eid , Grant Mathews

Known sources of lithium (Li) in the universe include the big bang, novae, asymptotic giant branch stars, and cosmic ray spallation. During their longer-lived evolutionary phases, stars are not expected to add to the Li budget of the…

Solar and Stellar Astrophysics · Physics 2022-07-20 Julio Chanamé , Marc H. Pinsonneault , Claudia Aguilera-Gómez , Joel C. Zinn

The bulk abundances of exoplanetesimals can be measured when they are accreted by white dwarfs. Recently, lithium from the accretion of exoplanetesimals was detected in relatively high levels in multiple white dwarfs. There are presently…

Earth and Planetary Astrophysics · Physics 2024-12-04 Benjamin C. Kaiser , J. Christopher Clemens , Simon Blouin , Erik Dennihy , Patrick Dufour , Ryan J. Hegedus , Joshua S. Reding

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

The disagreement between theoretical predictions and observations for surface lithium abundance in stars is a long-standing problem, which indicates that the adopted physical treatment is still lacking in some points. However, thanks to the…

Solar and Stellar Astrophysics · Physics 2015-06-11 E. Tognelli , S. Degl'Innocenti , P. G. Prada Moroni

The lithium plateau observed in halo stars has long appeared as a paradox in the general context of the lithium abundance behavior in stellar outer layers. First, the plateau is flat, second, the lithium abundance dispersion is extremely…

Astrophysics · Physics 2009-11-06 Sylvie Theado , Sylvie Vauclair

We adopt up-to-date yields of 7Li, 13C, 15N from classical novae and use a well tested model for the chemical evolution of the Milky Way in order to predict the temporal evolution of these elemental species in the solar neighborhood. In…

Astrophysics · Physics 2016-01-27 Donatella Romano , Francesca Matteucci
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