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We follow the Galactic enrichment of three easily observed light n-capture elements Sr,Y,and Zr.Input stellar yields have been first separated into their respective main and weak s-process,and r-process components.The s-process yields from…

Recent observations of r-process-enriched metal-poor star abundances reveal a non-uniform abundance pattern for elements $Z\leq47$. Based on non-correlation trends between elemental abundances as a function of Eu-richness in a large sample…

We present a comprehensive study of the abundance evolution of the elements from H to U in the Milky Way halo and local disk. We use a consistent chemical evolution model, metallicity dependent isotopic yields from low and intermediate mass…

Astrophysics of Galaxies · Physics 2018-02-21 N. Prantzos , C. Abia , M. Limongi , A. Chieffi , S. Cristallo

The decomposition of the Solar system abundances of heavy isotopes into their s- and r- components plays a key role in our understanding of the corresponding nuclear processes and the physics and evolution of their astrophysical sites. We…

Astrophysics of Galaxies · Physics 2020-01-08 N. Prantzos , C. Abia , S. Cristallo , M. Limongi , A. Chieffi

Many observed CEMP stars are found in binary systems and show enhanced abundances of $s$-elements. The origin of the chemical abundances of these CEMP-$s$ stars is believed to be accretion in the past of enriched material from a primary…

Solar and Stellar Astrophysics · Physics 2015-08-26 C. Abate , O. R. Pols , R. G. Izzard , A. I. Karakas

We follow the chemical evolution of the Galaxy for the s elements using a Galactic chemical evolution (GCE) model, as already discussed by Travaglio et al. (1999, 2001, 2004), with a full updated network and refined asymptotic giant branch…

Solar and Stellar Astrophysics · Physics 2014-11-20 A. Serminato , R. Gallino , C. Travaglio , S. Bisterzo , O. Straniero

We present first comparisons between Light Element Primary Process (LEPP) abundances observed in some ultra metal poor (UMP) stars and nucleosynthesis calculations based on long-time hydrodynamical simulations of core-collapse supernovae…

Astrophysics of Galaxies · Physics 2011-03-28 A. Arcones , F. Montes

Nucleosynthesis in the s process takes place in the He burning layers of low mass AGB stars and during the He and C burning phases of massive stars. The s process contributes about half of the element abundances between Cu and Bi in solar…

Solar and Stellar Astrophysics · Physics 2015-05-20 Franz Käppeler , Roberto Gallino , Sara Bisterzo , Wako Aoki

We study the s-process abundances (A > 90) at the epoch of the solar-system formation. AGB yields are computed with an updated neutron capture network and updated initial solar abundances. We confirm our previous results obtained with a…

Solar and Stellar Astrophysics · Physics 2015-06-19 S. Bisterzo , C. Travaglio , R. Gallino , M. Wiescher , F. Käppeler

A large sample of carbon enhanced metal-poor stars enriched in s-process elements (CEMP-s) have been observed in the Galactic halo. These stars of low mass (M ~ 0.9 Msun) are located on the main-sequence or the red giant phase, and do not…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. Bisterzo , R. Gallino , O. Straniero , S. Cristallo , F. Kaeppeler

We provide an individual analysis of 94 carbon enhanced metal-poor stars showing an s-process enrichment (CEMP-s) collected from the literature. The s-process enhancement observed in these stars is ascribed to mass transfer by stellar winds…

Solar and Stellar Astrophysics · Physics 2015-06-04 S. Bisterzo , R. Gallino , O. Straniero , S. Cristallo , F. Kaeppeler

During the evolution on the AGB, S-type stars are the first objects to experience s-process nucleosynthesis and third dredge-ups, and therefore to exhibit sprocess signatures in their atmospheres. Their significant mass loss rates (10^-7 to…

Solar and Stellar Astrophysics · Physics 2010-11-10 Pieter Neyskens , Sophie Van Eck , Bertrand Plez , Stéphane Goriely , Lionel Siess , Alain Jorissen

The knowledge of isotopic and elemental abundances of the pristine solar system material provides a fundamental test of galactic chemical evolution models, while the composition of the solar photosphere is a reference pattern to understand…

Astrophysics · Physics 2009-11-11 L. Piersanti , O. Straniero , S. Cristallo

Context. Barium (Ba) stars are dwarf and giant stars enriched in elements heavier than iron produced by the slow neutron-capture process (s process). They belong to binary systems where the primary star evolved through the asymptotic giant…

Solar and Stellar Astrophysics · Physics 2018-12-12 B. Cseh , M. Lugaro , V. D'Orazi , D. B. de Castro , C. B. Pereira , A. I. Karakas , L. Molnár , E. Plachy , R. Szabó , M. Pignatari , S. Cristallo

About half of carbon and s-process enhanced metal-poor stars (CEMP-s) show a high r-process enrichment (CEMP-s/r), incompatible with a pure s-process contribution. CEMP-s stars are of low mass (M < 0.9 Msun) and belong to binary systems.…

Solar and Stellar Astrophysics · Physics 2015-03-17 Sara Bisterzo , Roberto Gallino

From newly-obtained high-resolution, high signal-to-noise ratio spectra the abundances of the elements La and Eu have been determined over the stellar metallicity range -3<[Fe/H]<+0.3 in 159 giant and dwarf stars. Lanthanum is predominantly…

Astrophysics · Physics 2009-11-10 J. Simmerer , C. Sneden , J. J. Cowan , J. Collier , V. M. Woolf , J. E. Lawler

Analysis of inclusions in primitive meteorites reveals that several short-lived radionuclides (SLRs) with half-lives $0.1-100$ Myr existed in the early Solar System (ESS). We investigate the ESS origin of $^{107}$Pd, $^{135}$Cs, and…

Astrophysics of Galaxies · Physics 2022-01-12 T. C. L. Trueman , B. Côté , A. Yagüe López , J. den Hartogh , M. Pignatari , B. Soós , A. I. Karakas , M. Lugaro

We performed a detailed, high-resolution spectroscopic analysis of HE 1005-1439 based on SUBARU/HDS spectra with an R ~ 50000. Abundances of ten light elements from C through Ni and twelve heavy elements Sr, Y, Ba, La, Ce, Pr, Nd, Eu, Dy,…

Solar and Stellar Astrophysics · Physics 2022-01-05 Partha Pratim Goswami , Aruna Goswami

The considerable scatter of the s- and r-process elements observed in low-metallicity stars, compared to the small star to star scatter observed for the alpha elements, is an open question for the chemical evolution studies. We have…

Astrophysics · Physics 2007-05-23 G. Cescutti

To better characterize the abundance patterns produced by the r-process, we have derived new abundances or upper limits for the heavy elements zinc (Zn), yttrium (Y), lanthanum (La), europium (Eu), and lead (Pb). Our sample of 161…

Solar and Stellar Astrophysics · Physics 2015-05-20 I. U. Roederer , J. J. Cowan , A. I. Karakas , K. -L. Kratz , M. Lugaro , J. Simmerer , K. Farouqi , C. Sneden
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