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dc.contributor.authorBaraffe, I
dc.contributor.authorPratt, J
dc.contributor.authorGoffrey, T
dc.contributor.authorConstantino, T
dc.contributor.authorFolini, D
dc.contributor.authorPopov, MV
dc.contributor.authorWalder, R
dc.contributor.authorViallet, M
dc.date.accessioned2017-08-31T08:44:26Z
dc.date.issued2017-08-09
dc.description.abstractWe study lithium depletion in low-mass and solar-like stars as a function of time, using a new diffusion coefficient describing extra-mixing taking place at the bottom of a convective envelope. This new form is motivated by multi-dimensional fully compressible, time implicit hydrodynamic simulations performed with the MUSIC code. Intermittent convective mixing at the convective boundary in a star can be modeled using extreme value theory, a statistical analysis frequently used for finance, meteorology, and environmental science. In this letter, we implement this statistical diffusion coefficient in a one-dimensional stellar evolution code, using parameters calibrated from multi-dimensional hydrodynamic simulations of a young low-mass star. We propose a new scenario that can explain observations of the surface abundance of lithium in the Sun and in clusters covering a wide range of ages, from $\sim$ 50 Myr to $\sim$ 4 Gyr. Because it relies on our physical model of convective penetration, this scenario has a limited number of assumptions. It can explain the observed trend between rotation and depletion, based on a single additional assumption, namely that rotation affects the mixing efficiency at the convective boundary. We suggest the existence of a threshold in stellar rotation rate above which rotation strongly prevents the vertical penetration of plumes and below which rotation has small effects. In addition to providing a possible explanation for the long standing problem of lithium depletion in pre-main sequence and main sequence stars, the strength of our scenario is that its basic assumptions can be tested by future hydrodynamic simulations.en_GB
dc.description.sponsorshipThis work is funded by the ERC grant No. 320478-TOFU. It used the DiRAC Complexity system which is part of the STFC DiRAC HPC Facility (funded by BIS National E-Infrastructure capital grant ST/K000373/1 and Operations grant ST/K0003259/1). This work also used the University of Exeter Supercomputer ISCA.en_GB
dc.identifier.citationVol. 845 (1), article L6en_GB
dc.identifier.doi10.3847/2041-8213/aa82ff
dc.identifier.urihttp://hdl.handle.net/10871/29137
dc.language.isoenen_GB
dc.publisherAmerican Astronomical Society / IOP Publishingen_GB
dc.rights© 2017. The American Astronomical Society. All rights reserved.en_GB
dc.subjectconvectionen_GB
dc.subjecthydrodynamicsen_GB
dc.subjectstars: evolutionen_GB
dc.subjectstars: pre-main sequenceen_GB
dc.subjectstars: rotationen_GB
dc.subjectstars: solar-typeen_GB
dc.titleLithium depletion in solar-like stars: effect of overshooting based on realistic multi-dimensional simulationsen_GB
dc.typeArticleen_GB
dc.date.available2017-08-31T08:44:26Z
dc.descriptionThis is the final version of the article. Available from American Astronomical Society via the DOI in this record.en_GB
dc.identifier.journalAstrophysical Journal Lettersen_GB


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