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Solar twins in M 67: evolutionary status and lithium abundance
(EDP SCIENCES S A, 2011)
Aims. We determine the age and mass of the three best solar twin candidates in open cluster M 67 through lithium evolutionary models. Methods. We computed a grid of evolutionary models with non-standard mixing at metallicity ...
Mass effect on the lithium abundance evolution of open clusters: Hyades, NGC 752, and M67
(EDP Sciences, 2016-03-12)
Lithium abundances in open clusters provide an e ective way of probing mixing processes in the interior of solar-type stars and convection is not the only mixing mechanism at work. To understand which mixing mechanisms are ...
Spectral energy distribution analysis of class i and class ii fu orionis stars
(IOP Publishing, 2014-06)
FU Orionis stars (FUors) are eruptive pre-main sequence objects thought to represent quasi-periodic or recurring stages of enhanced accretion during the low-mass star-forming process. We characterize the sample of known ...
Possible signature of hypernova nucleosynthesis in a beryllium-rich halo dwarf
(WILEY-BLACKWELL, 2008)
As part of a large survey of halo and thick disc stars, we found one halo star, HD106038, exceptionally overabundant in beryllium. In spite of its low metallicity, [Fe/H] = -1.26, the star has log(Be/H) = -10.60, which is ...
On mode trapping in pulsating DA white dwarf stars
(Wiley Blackwell Publishing, Inc, 2002-09)
The effects are explored of time-dependent element diffusion on the mode-trapping properties of DA white dwarf models with various thicknesses of the hydrogen envelope. Our predictions are compared with the standard ...