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Related papers: Lithium in M67: From the main sequence to the red …

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This work aims to investigate the behaviour of the lithium abundance in stars with and without detected planets. Our study is based on a sample of 1332 FGK main-sequence stars with measured lithium abundances, for 257 of which planets were…

Solar and Stellar Astrophysics · Physics 2024-02-05 F. Llorente de Andrés , R. de la Reza , P. Cruz , D. Cuenda-Muñoz , E. J. Alfaro , C. Chavero , C. Cifuentes

In the globular cluster NGC2808, a quasi-standard initial lithium abundance is derived for a red giant belonging to the `extreme' population, characterized by a large helium overabundance, and by abundances of proton capture elements…

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

A five-dimensional interpolation method and corresponding computer program are developed for using published calculations to determine the non-LTE correction {\Delta\}NLTE to the lithium abundance log{\epsilon}(Li) derived from the Li I…

Solar and Stellar Astrophysics · Physics 2017-10-18 L. S. Lyubimkov , D. V. Petrov

The temperature distribution of field Li-rich red giants suggests the presence of a population of Li-rich red clump (RC) stars. One proposed explanation for this population is that all stars with masses near 2 $M_\odot$ experience a…

Solar and Stellar Astrophysics · Physics 2016-08-24 Joleen K. Carlberg , Katia Cunha , Verne V. Smith

Planet engulfment has been identified as one of the mechanisms for enhancing lithium abundance in stars. However, comprehensive investigations into lithium signatures following such events remain limited. Stars born together, sharing a…

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

Open clusters serve as laboratories to study and evaluate stellar evolution and Galactic chemical evolution models. Chemical peculiarities, such as lithium-rich giants, are rarely observed in these stellar systems. This work focuses on…

Accurate spectroscopic lithium abundances are essential in addressing a variety of open questions, such as the origin of a uniform lithium content in the atmospheres of metal-poor stars (Spite plateau) or the existence of a correlation…

Solar and Stellar Astrophysics · Physics 2020-07-01 A. Mott , M. Steffen , E. Caffau , K. G. Strassmeier

Lithium abundances are presented and discussed for 70 members of the 50 Myr old open cluster alpha Per. More than half of the abundances are from new high-resolution spectra. The Li abundance in the F-type stars is equal to its presumed…

Solar and Stellar Astrophysics · Physics 2015-05-19 Suchitra C. Balachandran , Sushma V. Mallik , David L. Lambert

Stellar models with masses ranging from 0.5 to $1.3~M_\odot$ were constructed in order to compare to young cluster observations of Li and of rotation velocities. The amount of Li depletion in cool stars is sensitive to the amount of…

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

The present work aims to examine in detail the depletion of lithium in solar twins to better constrain stellar evolution models and investigate its possible connection with exoplanets. We employ spectral synthesis in the region of the…

Solar and Stellar Astrophysics · Physics 2019-03-20 M. Carlos , J. Melendez , L. Spina , L. A. dos Santos , M. Bedell , I. Ramirez , M. Asplund , J. L. Bean , D. Yong , J. Yana Galarza , A. Alves-Brito

Context. Galactic red novae are thought to be produced in stellar mergers between non-compact stars, such as main-sequence stars and cool giants. They are hoped to help in explaining physical processes involved in common envelope evolution…

Solar and Stellar Astrophysics · Physics 2023-04-26 Tomek Kamiński , Mirek Schmidt , Marcin Hajduk , Aleksandra Kiljan , Inna Izviekova , Adam Frankowski

Lithium is created during the Big Bang nucleosynthesis and it is destroyed in stellar interiors at relatively low temperatures. However, it should be preserved in the stellar envelopes of unevolved stars and progressively diluted during…

Solar and Stellar Astrophysics · Physics 2020-03-02 N. Sanna , E. Franciosini , E. Pancino , A. Mucciarelli

Context: Lithium is a fragile element, which is easily destroyed in the stellar interior. The existence of lithium-rich giants still represents a challenge for stellar evolution models. Aims: We have collected a large database of…

Solar and Stellar Astrophysics · Physics 2015-05-27 L. Monaco , S. Villanova , C. Moni Bidin , G. Carraro , D. Geisler , P. Bonifacio , O. A. Gonzalez , M. Zoccali , L. Jilkova

We present Li and Fe abundances for 87 stars in the GC M4,obtained with GIRAFFE high-resolution spectra. The targets range from the TO up to the RGB Bump. The Li abundance in the TO stars is uniform, with an average value A(Li)=2.30+-0.02…

Solar and Stellar Astrophysics · Physics 2015-05-20 A. Mucciarelli , M. Salaris , L. Lovisi , F. R. Ferraro , L. Lanzoni , S. Lucatello , R. G. Gratton

Measurements of lithium (Li) abundances in open clusters provide a unique tool for following the evolution of this element with age, metallicity, and stellar mass. Using FLAMES/Giraffe on the VLT, we obtained spectra of 157 candidate…

Solar and Stellar Astrophysics · Physics 2009-11-13 S. Randich , G. Pace , L. Pastori , A. Bragaglia

In recent years much interest has been shown in the process of thermohaline mixing in red giants. In low and intermediate mass stars this mechanism first activates at the position of the bump in the luminosity function, and has been…

Solar and Stellar Astrophysics · Physics 2015-06-23 John Lattanzio , Lionel Siess , Ross Church , George Angelou , Richard Stancliffe , Carolyn Doherty , Thomas Stephen , Simon Campbell

We present spectroscopic observations of candidate F, G and K type stars in NGC 6633, an open cluster with a similar age to the Hyades. We identify 10 new cluster members including one short period binary system. Combining this survey with…

Astrophysics · Physics 2009-11-07 R. D. Jeffries , E. J. Totten , S. Harmer , C. P. Deliyannis

Planetary engulfment events have long been proposed as a lithium (Li) enrichment mechanism contributing to the population of Li-rich giants (A(Li) >= 1.5 dex). Using MESA stellar models and A(Li) abundance measurements obtained by the GALAH…

Solar and Stellar Astrophysics · Physics 2021-12-08 M. Soares-Furtado , Matteo Cantiello , Morgan MacLeod , Melissa K. Ness
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