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

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Reconstructing the Galactic evolution of lithium (Li) is the main tool used to constrain the source(s) of Li enrichment in the Galaxy. Recent results have suggested a decline in Li at supersolar metallicities, which may indicate reduced…

Lithium abundances are presented for 91 dwarf and subgiant stars in the Galactic bulge. The analysis is based on line synthesis of the 7Li line at 6707 {\AA} in high-resolution spectra obtained during gravitational microlensing events, when…

Astrophysics of Galaxies · Physics 2020-02-26 T. Bensby , S. Feltzing , J. C. Yee , J. A. Johnson , A. Gould , M. Asplund , J. Meléndez , S. Lucatello

The earliest phases of the chemical evolution of our Galaxy are analysed in the light of the recent VLT results (concerning abundance patterns in the most metal-poor stars of the Galactic halo) and of stellar nucleosynthesis calculations.…

Astrophysics · Physics 2009-11-10 Nikos Prantzos

We revisit large spectroscopic data sets for field stars from the literature to derive the upper Li envelope in the high metallicity regime in our Galaxy. We take advantage of Gaia EDR3 data and state-of-the-art stellar models to precisely…

Astrophysics of Galaxies · Physics 2021-05-12 C. Charbonnel , S. Borisov , N. Prantzos , P. De Laverny

The chemical separation of Li+ ions induced by a magnetic field during the hierarchical structure formation can reduce initial Li abundances in cosmic structures. It is shown that cosmological reionization of neutral Li atoms quickly…

Solar and Stellar Astrophysics · Physics 2019-05-15 Motohiko Kusakabe , Masahiro Kawasaki

The detection of $^6$Li in Spite plateau stars contradicts the standard Big Bang nucleosynthesis prediction, known as the second cosmological lithium problem. We measure the isotopic ratio $^6$Li/$^7$Li in three Spite plateau stars: HD…

Solar and Stellar Astrophysics · Physics 2021-10-20 E. X. Wang , T. Nordlander , M. Asplund , K. Lind , Y. Zhou , H. Reggiani

The early chemical evolution of the Galaxy and the Universe is vital to our understanding of a host of astrophysical phenomena. Since the most metal-poor Galactic stars (with metallicities down to [Fe/H]\sim-5.5) are relics from the…

Astrophysics of Galaxies · Physics 2015-05-30 Anna Frebel

Metal-poor stars are crucially important for understanding the early Galaxy, first stars, and the Universe. In this series of papers, we present a homogeneous non-local thermodynamic equilibrium (NLTE) abundances analysis of 12 elements for…

Big-bang nucleosynthesis (BBN) theory, together with the precise WMAP cosmic baryon density, makes tight predictions for the abundances of the lightest elements. Deuterium and 4He measurements agree well with expectations, but 7Li…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-19 Brian D. Fields

Mapping lithium evolution for evolved stars will provide restrictions and constraints on the fundamental stellar interior physical processes, which further shed light on our understanding of the theory of stellar structure and evolution.…

Solar and Stellar Astrophysics · Physics 2021-09-29 Jinghua Zhang , Jian-Rong Shi , Hong-Liang Yan , Yaguang Li , Qi Gao , Chun-Qian Li , Xianfei Zhang , Shuai Liu , Shaolan Bi , Gang Zhao , Yan Li

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…

We present a study on the detailed elemental abundances of newly identified bright very metal-poor stars with the detection of lithium, initially observed as part of the SDSS/MARVELS pre-survey. These stars were selected for high-resolution…

Solar and Stellar Astrophysics · Physics 2022-10-05 Avrajit Bandyopadhyay , Thirupathi Sivarani , Timothy C. Beers , A. Susmitha , Prasanta K Nayak , Jeewan C Pandey

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…

We have studied 23 very metal-poor field turnoff stars, specifically chosen to enable a precise measurement of the dispersion in the lithium abundance of the Spite Li plateau. We concentrated on stars having a narrow range of effective…

Astrophysics · Physics 2009-10-31 Sean G. Ryan , John E. Norris , Timothy C. Beers

We adopt up-to-date 7Li yields from asymptotic giant branch stars in order to study the temporal evolution of 7Li in the solar neighbourhood in the context of a revised version of the two-infall model for the chemical evolution of our…

Astrophysics · Physics 2016-08-30 Donatella Romano , Francesca Matteucci , Paolo Ventura , Francesca D'Antona

We reconsider the role of pre-main sequence (pre-MS) Li depletion on the basis of new observational and theoretical evidence: i) new observations of Halpha emissions in young clusters show that mass accretion could be continuing till the…

Solar and Stellar Astrophysics · Physics 2012-06-07 P. Molaro , A. Bressan , M. Barbieri , P. Marigo , S. Zaggia

The abundance of primordial lithium is derived from the observed spectroscopy of metal-poor stars in the galactic halo. However, the observationally inferred abundance remains at about a factor of three below the abundance predicted by…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-30 G. J. Mathews , A. Kedia , N. Sasankan , M. Kusakabe , Y. Luo , T. Kajino , D. G. Yamazaki , T. Makki , M. El Eid

Most of relatively warm, unevolved metal-poor stars ($T_{\rm eff}\gtrsim 5800\,\mathrm{K}$ and $[{\rm Fe/H}]\lesssim -1.5$) exhibit almost constant lithium abundances, irrespective of metallicity or effective temperature, and thus form the…

Solar and Stellar Astrophysics · Physics 2017-06-21 Tadafumi Matsuno , Wako Aoki , Takuma Suda , Haining Li

The discrepancy between the theoretical prediction of primordial lithium abundances and astronomical observations is called the Lithium Problem. We find that extra contributions from non-thermal hydrogen and helium during Big Bang…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-31 Ming-Ming Kang , Yang Hu , Hong-Bo Hu , Shou-Hua Zhu
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