English
Related papers

Related papers: The diffusive overshooting approach on Li abundanc…

200 papers

We present Li abundances for 14 solar-type stars in the intermediate age (~ 2 Gyr) clusters IC 4651 and NGC 3680. The log n(Li) vs. effective temperature distributions are compared with those of the similar age cluster NGC 752, of the…

Astrophysics · Physics 2007-05-23 S. Randich , L. Pasquini , R. Pallavicini

In this paper, four sets of evolutionary models are computed with different values of the mixing length parameter $\alpha_{\rm p}$ and the overshooting parameter $\delta_{\rm ov}$. The properties of the convective cores and the convective…

Solar and Stellar Astrophysics · Physics 2015-05-14 Jin Jie , Chunhua Zhu , Guoliang Lv

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

We report on the abundance analysis of Li in solar-type (G-type main sequence) superflare stars which were found by the analysis of Kepler photometric data. Li is a key element to understand the evolution of the stellar convection zone…

Solar and Stellar Astrophysics · Physics 2015-07-15 Satoshi Honda , Yuta Notsu , Hiroyuki Maehara , Shota Notsu , Takuya Shibayama , Daisaku Nogami , Kazunari Shibata

The precise measurement of the masses and radii of stars in eclipsing binary systems provides a window into uncertain processes in stellar evolution, especially mixing at convective boundaries. Recently, these data have been used to…

Solar and Stellar Astrophysics · Physics 2018-10-31 Thomas Constantino , Isabelle Baraffe

As part of an ongoing program to measure detailed chemical abundances in nearby galaxies, we use a sample of young to intermediate age clusters in the Large Magellanic Cloud with ages of 10 Myr to 2 Gyr to evaluate the effect of isochrone…

Solar and Stellar Astrophysics · Physics 2015-06-04 J. E. Colucci , R. A. Bernstein

The detached eclipsing binary stars with convective cores provide a good tool to investigate the convective core overshoot. It has been performed on some binary stars to restrict the classical overshoot model which simply extends the…

Solar and Stellar Astrophysics · Physics 2015-06-19 Y. Meng , Q. S. Zhang

Most phenomenological galaxy formation models show a discrepancy between the predicted Tully-Fisher relation and the luminosity function. We show that this is mainly due to overmerging of galaxy haloes, which is inherent in both the…

Astrophysics · Physics 2007-05-23 Eelco van Kampen

We investigate the history of $^6$Li and $^7$Li in population II dwarfs during the pre main sequence and main sequence. The evolution is followed using the CESAM code and taking into account the most recent physics. The effective…

Astrophysics · Physics 2007-05-23 Laurent Piau

The Sun is the most studied of all stars. It is a reference for all other observed stars and a laboratory of fundamental physics helping us understand processes occuring in conditions irreproducible on Earth. However, our understanding of…

Double-line eclipsing binaries (DLEBs) have been recently used to constrain the amount of central mixing as a function of stellar mass, with contrasting results. In this work, we reanalyze the DLEB sample by Claret & Torres, using a…

Solar and Stellar Astrophysics · Physics 2019-03-20 Guglielmo Costa , Léo Girardi , Alessandro Bressan , Paola Marigo , Thaíse S. Rodrigues , Yang Chen , Antonio Lanza , Paul Goudfrooij

Thermohaline mixing is a favoured mechanism for the so-called "extra mixing" on the red giant branch of low-mass stars. The mixing is triggered by the molecular weight inversion created above the hydrogen shell during first dredge-up when…

Solar and Stellar Astrophysics · Physics 2017-06-28 Kate Henkel , Amanda I. Karakas , John C. Lattanzio

The uncertainties in the modelling of some important inputs of stellar evolution must be taken into account for a correct interpretation, both of the HR diagrams of individual stars, and of the integrated colors, of stellar clusters. After…

Astrophysics · Physics 2007-05-23 F. D'Antona

Improvements induced by helioseismology show that microscopic diffusion cannot be neglected in solar models. Helium and metal diffusion is now generally introduced in the computations. They cannot however explain the observed lithium…

Astrophysics · Physics 2007-05-23 Sylvie Vauclair , Olivier Richard

In the overshoot mixing model with an exponentially decreasing diffusion coefficient, the initial value of the diffusion coefficient plays a crucial role. According to the turbulent convective mixing model, the characteristic length of…

Solar and Stellar Astrophysics · Physics 2023-08-09 Qian-Sheng Zhang , Li Yan , Wu Tao , Jiang Chen

We determine lithium (Li) abundances for solar twins in the M67 open cluster to add valuable information about the correlation between Li depletion and stellar age and, then, better understand stellar structure and evolution. We use high…

Solar and Stellar Astrophysics · Physics 2020-01-08 Marilia Carlos , Jorge Melendez , Jose-Dias do Nascimento , Matthieu Castro

Old open clusters are very useful targets to investigate mechanisms responsible for lithium (Li) depletion during the main sequence. Comparison of the Li abundances in clusters of different age allows us to understand the efficiency of the…

Astrophysics · Physics 2009-11-13 Loredana Prisinzano , Sofia Randich

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

We discuss the effects of convective overshooting in the PMS evolution of intermediate mass stars, by analysing in detail the early evolution towards the main sequence of a 2 M_sun stellar model. These effects can be extremely important in…

Astrophysics · Physics 2009-11-11 J. P. Marques , M. J. P. F. G. Monteiro , J. Fernandes

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