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Related papers: Y2 Isochrones with an Improved Core Overshoot

200 papers

Context. Mixing by convective overshooting has long been suggested to play an important role for the amount of hydrogen available to nuclear burning in convective cores of stars. The best way to model this effect is still debated. Aims. We…

Solar and Stellar Astrophysics · Physics 2022-11-16 F. Kupka , F. Ahlborn , A. Weiss

We study prospects for seismic sounding the layer of a partial mixing above the convective core in main-sequence stars with masses in the 1.2 -- 1.9 solar mass range. There is an initial tendency to an increase of convective core mass in…

Astrophysics · Physics 2007-05-23 B. L. Popielski , W. A. Dziembowski

We present a dense grid of evolutionary tracks and isochrones of rotating massive main-sequence stars. We provide three grids with different initial compositions tailored to compare with early OB stars in the Small and Large Magellanic…

The evolution of stars born with a convective core is highly dependent on the efficiency and extent of near core mixing processes, which effectively increases both the core mass and main-sequence lifetime. We investigate to what extent…

Solar and Stellar Astrophysics · Physics 2018-07-04 M. G. Pedersen , C. Aerts , P. I. Pápics , T. M. Rogers

We study the dynamical evolution of star clusters on eccentric orbits using a semi-analytical approach. In particular we adapt and extend the equations of EMACSS code, introduced by Gieles et al. (2014), to work with eccentric orbits. We…

Astrophysics of Galaxies · Physics 2019-04-23 Hamid Ebrahimi , Hosein Haghi , Pouria Khalaj , Akram Hasani Zonoozi , Ghasem Safaei

We present an analysis of the response of a radiative region to waves generated by a convective region of the star; this wave treatment of the classical problem of ``overshooting'' gives extra mixing relative to the treatment traditionally…

Astrophysics · Physics 2009-11-07 Patrick A. Young , Karen A. Knierman , Jane R. Rigby , David Arnett

The focus of this study is on the treatment of those stellar regions immediately adjacent to convective zones. The results of hydrodynamical simulations by Freytag et al. (1996, A&A313,497) show that the motion of convective elements…

Astrophysics · Physics 2007-05-23 F. Herwig , T. Blöcker , D. Schönberner , M. El Eid

In a robust statistical way, we quantify the uncertainty that affects the calibration of the overshooting efficiency parameter $\beta$ that is owing to the uncertainty on the observational data in double-lined eclipsing binary systems. We…

Solar and Stellar Astrophysics · Physics 2016-02-17 G. Valle , M. Dell'Omodarme , P. G. Prada Moroni , S. Degl'Innocenti

We briefly review the main problems related to the computation of the evolution of intermediate-mass stars: the treatment of turbulent convection and the occurrence of blue loops during the core He-burning phase. It is shown that, in order…

Astrophysics · Physics 2007-05-23 S. Cassisi

We have investigated the role of the convective overshooting on the production of s-nuclei during core He-burning phase in stellar models with different initial mass and metallicity ($15 \leq M_{ZAMS}/M_{\odot} \leq 25$; $10^{-4} \leq Z…

Solar and Stellar Astrophysics · Physics 2011-09-09 M. L. Pumo , G. Contino , A. Bonanno , R. A. Zappalà

The convective envelopes of solar-type stars and the convective cores of intermediate- and high-mass stars share boundaries with stable radiative zones. Through a host of processes we collectively refer to as "convective boundary mixing"…

Solar and Stellar Astrophysics · Physics 2023-04-18 Evan H. Anders , May G. Pedersen

Convective boundary mixing (CBM) is ubiquitous in stellar evolution. It is a necessary ingredient in the models in order to match observational constraints from clusters, binaries and single stars alike. We compute `effective overshoot'…

Solar and Stellar Astrophysics · Physics 2020-02-19 George C Angelou , Earl P. Bellinger , Saskia Hekker , Yvonne Elsworth , Sarbani Basu , Achim Weiss

We improve the current upper bound on the axion-photon coupling derived from stellar evolution using the $R_2$ parameter, the ratio of stellar populations on the Asymptotic Giant Branch to Horizontal Branch in Globular Clusters. We compare…

High Energy Physics - Phenomenology · Physics 2022-11-28 Matthew J. Dolan , Frederick J. Hiskens , Raymond R. Volkas

We present the results of 3--D simulations of core convection within A-type stars of 2 solar masses, at a range of rotation rates. We consider the inner 30% by radius of such stars, thereby encompassing the convective core and some of the…

Astrophysics · Physics 2008-11-26 Matthew Browning , Allan Sacha Brun , Juri Toomre

Context: We study the impact of two-dimensional spherical shells on compressible convection. Realistic profiles for density and temperature from a one-dimensional stellar evolution code are used to produce a model of a large stellar…

Solar and Stellar Astrophysics · Physics 2016-10-05 J. Pratt , I. Baraffe , T. Goffrey , C. Geroux , M. Viallet , D. Folini , T. Constantino , M. Popov , R. Walder

We calculated a grid of evolutionary tracks of rotating models with masses between 1.0 and 3.0 $M_{\odot}$ and a resolution $\delta M \leq 0.02$ $M_{\odot}$, which can be used to study the effects of rotation on stellar evolutions and on…

Solar and Stellar Astrophysics · Physics 2015-06-12 Wuming Yang , Shaolan Bi , Xiangcun Meng

We assess the systematic uncertainties in stellar evolutionary calculations for low- to intermediate-mass, main-sequence stars. We compare published stellar tracks from several different evolution codes with our own tracks computed using…

Solar and Stellar Astrophysics · Physics 2016-02-17 R. J. Stancliffe , L. Fossati , J. -C. Passy , F. R. N. Schneider

We present four large sets of evolutionary tracks for stars with initial chemical compositions [Y=0.250, Z=0.008], [Y=0.273, Z=0.019], [Y=0.320, Z=0.040] and [Y=0.390, Z=0.070] and enhancement of alpha elements with respect to the solar…

Astrophysics · Physics 2007-05-23 Bernardo Salasnich , Leo Girardi , Achim Weiss , Cesare Chiosi

We present a large grid of stellar evolutionary tracks, which are suitable to modelling star clusters and galaxies by means of population synthesis. The tracks are presented for the initial chemical compositions [Z=0.0004, Y=0.23],…

Astrophysics · Physics 2009-05-29 Leo Girardi , Alessandro Bressan , Gianpaolo Bertelli , Cesare Chiosi

The extent of mixed regions around convective zones is one of the biggest uncertainties in stellar evolution. 1D overshooting descriptions introduce a free parameter ($f_{ov}$) that is in general not well constrained from observations.…

Solar and Stellar Astrophysics · Physics 2021-03-08 Johann Higl , Ewald Mueller , Achim Weiss