New Asymptotic Giant Branch models for a range of metallicities (2009)
Weiss, Achim, Ferguson, Jason W.
We present a new grid of stellar model calculations for stars on the Asymptotic Giant Branch between 1.0 and 6.0 M_sun. Our grid consists of 5 chemical mixtures between Z=0.0005 and Z=0.04, with both...
Salaris, Maurizio, Serenelli, Aldo, Weiss, Achim, Bertolami, Marcelo Miller
Using the most recent results about white dwarfs in 10 open clusters, we revisit semi-empirical estimates of the initial-final mass relation in star clusters, with emphasis on the use of stellar...
Lebreton, Yveline, Montalban, Josefina, Christensen-Dalsgaard, Joergen, Roxburgh, Ian W., Weiss, Achim
We compare stellar models produced by different stellar evolution codes for the CoRoT/ESTA project, comparing their global quantities, their physical structure, and their oscillation properties. We...
Lebreton, Yveline, Montalbán, Josefina, Christensen-Dalsgaard, Jørgen, Roxburgh, Ian W., Weiss, Achim
Hydrodynamic simulations of the core helium flash (2008)
Mocák, Miroslav, Müller, Ewald, Weiss, Achim, Kifonidis, Konstantinos
Fine Structure of the Red Giant Clump From (2007)
Hipparcos Data And, Achim Weiss, Maurizio Salaris
. The I-band brightness M I of clump stars is a possible distance indicator for stellar populations. Investigations have shown that M I is almost insensitive to the (V \Gamma I) colour within the...
Evolutionary tracks and isochrones for ff-enhanced stars (2007)
Bernardo Salasnich, Achim Weiss, Cesare Chiosi
A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are:
Round table discussion on session D: stellar evolution, nucleosynthesis and convective mixing (2007)
Cox & Giuli's principles of stellar structure (2004)
Weiss, Achim, Hillebrandt, W., Thomas, Hans-Christoph, Ritter, Hans
The age of the oldest Open Clusters (2003)
Salaris, Maurizio, Weiss, Achim, Percival, Susan M.
We determine ages of 71 old Open Clusters by a two-step method: we use main-squence fitting to 10 selected clusters, in order to obtain their distances, and derive their ages from comparison with our...
Spectroscopic study of blue compact galaxies III. Empirical population synthesis (2003)
Kong, Xu, Charlot, Stephane, Weiss, Achim, Cheng, Fuzhen
This is the third paper of a series dedicated to the study of the star formation rates, star formation histories, metallicities and dust contents of a sample of blue compact galaxies (BCGs). We...
The HE flash in ultra metal-poor low-mass stars (2003)
Schlattl, Helmut, Salaris, Maurizio, Cassisi, Santi, Weiss, Achim
A contribution of 26Al to the O-Al anticorrelation in globular cluster red giants (2001)
Denissenkov, Pavel A., Weiss, Achim
We modify our combined ("deep mixing" plus "primordial") scenario explaining the star-to-star abundance variations in globular cluster red giants in such a way that it confirms with new experimental...
Atomic diffusion in metal-poor stars: II. Predictions for the Spite plateau (2001)
Salaris, Maurizio, Weiss, Achim
We have computed a grid of up-to-date stellar evolutionary models including atomic diffusion, in order to study the evolution with time of the surface Li abundance in low-mass metal-poor stars. We...
Evolutionary tracks and isochrones for alpha-enhanced stars (2000)
Salasnich, Bernardo, Girardi, Leo, Weiss, Achim, Chiosi, Cesare
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...
Evolution and surface abundances of red giants experiencing deep mixing (2000)
Weiss, Achim, Denissenkov, Pavel A., Charbonnel, Corinne
We have calculated the evolution of low metallicity red giant stars under the assumption of deep mixing between the convective envelope and the hydrogen burning shell. We find that the extent of the...
Age-luminosity relations for low-mass metal-poor stars (1999)
Weiss, Achim, Schlattl, Helmut
We present a grid of evolutionary calculations for metal-poor low-mass stars for a variety of initial helium and metal abundances. The intention is mainly to provide a database for deriving directly...
Colour transformations for isochrones in the VI-plane (1999)
Weiss, Achim, Salaris, Maurizio
Reliable temperature-colour transformations are a necessary ingredient for isochrones to be compared with observed colour-magnitude-diagrams of globular clusters. We show that both theoretical and...
Helioseismological constraint on solar axion emission (1998)
Schlattl, Helmut, Weiss, Achim, Raffelt, Georg
Helioseismological sound-speed profiles severely constrain possible deviations from standard solar models, allowing us to derive new limits on anomalous solar energy losses by the Primakoff emission...
Salaris, Maurizio, Weiss, Achim
New age determinations of the galactic disk globular clusters 47 Tuc, M71 and NGC6352 have been performed with our up-to-date alpha-enhanced stellar models. We find that all three clusters are about...
The age of the most nearby star (1997)
Weiss, Achim, Schlattl, Helmut
We address the question how accurately stellar ages can be determined by stellar evolution theory. We select the star with the best observational material available - our Sun. We determine the solar...
Chronology of the halo globular cluster system formation (1997)
Salaris, Maurizio, Weiss, Achim
Using up-to-date stellar models and isochrones we determine the age of 25 galactic halo clusters. The clusters are distributed into four groups according to metallicity. We measure the absolute age...
3He in stars of low and intermediate mass (1995)
Weiss, Achim, Wagenhuber, Josef, Denissenkov, Pavel A.
We follow the evolution of 3He in stars of mass 0.8 -- 10 M (solar units) for Pop. I and II compositions from the main sequence until advanced stages on the AGB. Under standard assumptions we confirm...
Bartelmann, Matthias, Steinmetz, Matthias, Weiss, Achim
We construct a sample of numerical models for clusters of galaxies and employ these to investigate their capability of imaging background sources into long arcs. Emphasis is laid on the statistics of...