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We investigate the validity of the core mass - luminosity relation (CMLR), originally described by Paczynski (1970), for asymptotic giant branch stars under the presence of third dredge-up events. We find, that models with efficient third dredge-up with less massive cores than those associated with hot bottom burning (Bloecker and Schoenberner 1991) do not obey the linear CMLR. Complete evolutionary calculations of thermal pulse stellar models which consider overshoot according to an exponential diffusive algorithm show systematically larger third dredge-up for lower core masses (0.55 Msol < M_H < 0.8 Msol) than any other existing models. We present and discuss the luminosity evolution of these models.
We searched for Technetium (Tc) in a sample of bright oxygen-rich asymptotic giant branch (AGB) stars located in the outer galactic bulge. Tc is an unstable element synthesised via the s-process in deep layers of AGB stars, thus it is a reliable indi
High dispersion near-infrared spectra have been taken of seven highly-evolved, variable, intermediate-mass (4-6 Msun) AGB stars in the LMC and SMC in order to look for C, N and O variations that are expected to arise from third dredge-up and hot-bott
As part of a reanalysis of Galactic Asymptotic Giant Branch stars (hereafter AGB stars) at infrared wavelengths, we discuss here two samples (the first of carbon-rich stars, the second of S stars) for which photometry in the near- and mid-IR and dist
The spectro-photometric properties of galaxies in galaxy formation models are obtained by combining the predicted history of star formation and mass accretion with the physics of stellar evolution through stellar population models. In the recent lite
We calculated models of massive AGB stars with a self-consistent coupling of time-dependent mixing and nuclear burning for 30 isotopes and 74 reactions. Overshoot with an exponentially declining velocity field was considered and applied during all st