Flash‐Driven Convective Mixing in Low‐Mass, Metal‐deficient Asymptotic Giant Branch Stars: A New Paradigm for Lithium Enrichment and a Possibles‐Process

2004 ◽  
Vol 602 (1) ◽  
pp. 377-387 ◽  
Author(s):  
Nobuyuki Iwamoto ◽  
Toshitaka Kajino ◽  
Grant J. Mathews ◽  
Masayuki Y. Fujimoto ◽  
Wako Aoki
Keyword(s):  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
New Paradigm ◽  
Convective Mixing ◽  
Low Mass ◽  
Giant Branch Stars ◽  
Lithium Enrichment

Evolution and Nucleosynthesis in Low‐Mass Asymptotic Giant Branch Stars. I. Formation of Population I Carbon Stars

1997 ◽  
Vol 478 (1) ◽  
pp. 332-339 ◽  
Author(s):  
Oscar Straniero ◽  
Alessandro Chieffi ◽  
Marco Limongi ◽  
Maurizio Busso ◽  
Roberto Gallino ◽  
...  
Keyword(s):  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Carbon Stars ◽  
Low Mass ◽  
Giant Branch Stars

scholarly journals EVOLUTION OF THERMALLY PULSING ASYMPTOTIC GIANT BRANCH STARS. IV. CONSTRAINING MASS LOSS AND LIFETIMES OF LOW MASS, LOW METALLICITY AGB STARS

2014 ◽  
Vol 790 (1) ◽  
pp. 22 ◽  
Author(s):  
Philip Rosenfield ◽  
Paola Marigo ◽  
Léo Girardi ◽  
Julianne J. Dalcanton ◽  
Alessandro Bressan ◽  
...  
Keyword(s):  
Mass Loss ◽  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Agb Stars ◽  
Low Metallicity ◽  
Low Mass ◽  
Giant Branch Stars

scholarly journals EVOLUTION, NUCLEOSYNTHESIS, AND YIELDS OF LOW-MASS ASYMPTOTIC GIANT BRANCH STARS AT DIFFERENT METALLICITIES

2009 ◽  
Vol 696 (1) ◽  
pp. 797-820 ◽  
Author(s):  
S. Cristallo ◽  
O. Straniero ◽  
R. Gallino ◽  
L. Piersanti ◽  
I. Domínguez ◽  
...  
Keyword(s):  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Low Mass ◽  
Giant Branch Stars

scholarly journals Extremely Metal-Poor Asymptotic Giant Branch Stars

Universe ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 44
Author(s):  
Mario Cirillo ◽  
Luciano Piersanti ◽  
Oscar Straniero
Keyword(s):  
Physical Structure ◽  
Asymptotic Giant Branch ◽  
Chemical Pollution ◽  
Asymptotic Giant Branch Stars ◽  
Chemical Abundances ◽  
First Stars ◽  
Convective Mixing ◽  
Nearby Galaxies ◽  
Complete Set ◽  
Giant Branch Stars

Little is known about the first stars, but hints on this stellar population can be derived from the peculiar chemical composition of the most metal-poor objects in the Milky Way and in resolved stellar populations of nearby galaxies. In this paper, we review the evolution and nucleosynthesis of metal-poor and extremely metal-poor (EMP) stars with low and intermediate masses. In particular, new models of 6 M⊙ with three different levels of metallicity, namely Z=10−4, 10−6 and 10−10, are presented. In addition, we illustrate the results obtained for a 2 M⊙, Z=10−5 model. All these models have been computed by means of the latest version of the FuNS code. We adopted a fully coupled scheme of solutions for the complete set of differential equations describing the evolution of the physical structure and the chemical abundances, as modified by nuclear processes and convective mixing. The scarcity of CNO in the material from which these stars formed significantly affects their evolution, their final fate and their contribution to the chemical pollution of the ISM in primordial galaxies. We show the potential of these models for the interpretation of the composition of EMP stars, with particular emphasis on CEMP stars.

scholarly journals The Chemical Composition of Asymptotic Giant Branch Stars-the s-process

1991 ◽  
Vol 145 ◽  
pp. 299-316
Author(s):  
David L. Lambert
Keyword(s):  
Chemical Composition ◽  
Solar System ◽  
Neutron Source ◽  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Agb Stars ◽  
Intermediate Mass ◽  
Low Mass ◽  
Giant Branch Stars

This review discusses the chemical composition of AGB stars in the light of predictions for intermediate-mass (3-8 M⊙, 22Ne(α,n) = the neutron source) and low-mass (< 3 M⊙, 13C(α,n) = the neutron source) stars. LM-AGB models can be constructed with envelopes having a composition quite similar to that of solar system material, the SiC grains recently discovered in meteorites, and real AGB stars in the sequence of spectral types M → S → C. Stellar counterparts of the IM-AGB models have yet to be discovered.

scholarly journals Lithium production by thermohaline mixing in low-mass, low-metallicity asymptotic giant branch stars

2009 ◽  
Vol 5 (S268) ◽  
pp. 405-410
Author(s):  
Richard J. Stancliffe ◽  
George C. Angelou ◽  
John C. Lattanzio
Keyword(s):  
Main Sequence ◽  
Asymptotic Giant Branch ◽  
Asymptotic Giant Branch Stars ◽  
Agb Stars ◽  
Low Metallicity ◽  
Low Mass ◽  
Thermal Pulses ◽  
Giant Branch Stars

AbstractWe examine the effects of thermohaline mixing on the composition of the envelopes of low-metallicity asymptotic giant branch (AGB) stars. We have evolved models of 1, 1.5 and 2M⊙ and of metallicity Z = 10−4 from the pre-main sequence to the end of the thermal pulsing asymptotic giant branch with thermohaline mixing applied throughout the simulations. We find that the small amount of 3He that remains after the first giant branch is enough to drive thermohaline mixing on the AGB and that the mixing is most efficient in the early thermal pulses, with the efficiency dropping from pulse to pulse. We note a surprising increase in the 7Li abundance, with log10ϵ(7Li) reaching values of over 2.5 in the 1.5M⊙ model. It is thus possible to get stars which are both C- and Li-rich at the same time. We compare our models to measurements of carbon and lithium in carbon-enhanced metal-poor stars which have not yet reached the giant branch. These models can simultaneously reproduced the observed C and Li abundances of carbon-enhanced metal-poor turn-off stars that are Li-rich.

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