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Related papers: The i-process and CEMP-r/s stars

200 papers

Nuclear astrophysics simulations aiming to study the origin of the elements in stars require a multitude of nuclear physics input. Both systematic model dependent and statistically correlated uncertainties need to be considered. An…

Solar and Stellar Astrophysics · Physics 2013-10-18 M. G. Bertolli , F. Herwig , M. Pignatari , T. Kawano

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

The chemical abundances of the very metal-poor double-enhanced stars are excellent information for setting new constraints on models of neutron-capture processes at low metallicity. These stars are known as s+r stars, since they show…

Astrophysics · Physics 2009-11-11 Bo Zhang , Kun Ma , Guide Zhou

The chemical abundances of the metal-poor stars in the stellar stream provide important information for setting constraints on models of neutron-capture processes. The study of these stars could give us a better understanding of r-process…

Solar and Stellar Astrophysics · Physics 2015-06-11 Hongjie Li , Shuai Liang , Wenyuan Cui , Bo Zhang

(Abridged) The CEMP--no stars are "carbon-enhanced-metal-poor" stars that in principle show no evidence of s-- and r--elements from neutron captures. We try to understand the origin and nucleosynthetic site of their peculiar CNO, Ne--Na,…

Solar and Stellar Astrophysics · Physics 2015-04-01 Andre Maeder , Georges Meynet , Cristina Chiappini

In order to get a broader view of the s-process nucleosynthesis we study the abundance distribution of heavy elements of 35 barium stars and 24 CEMP-stars, including nine CEMP-s stars and 15 CEMP-r/s stars. The similar distribution of…

Solar and Stellar Astrophysics · Physics 2013-05-09 Wenyuan Cui , Jianrong Shi , Yuanyuan Geng , Caixia Zhang , Xiaoying Meng , Lang Shao , Bo Zhang

The evolution of central stars of planetary nebulae can proceed in several distinct ways, either leading to H-deficiency or to H-normal surface composition. Several new simulations of the evolution channels that lead to H-deficiency are now…

Astrophysics · Physics 2009-11-11 Falk Herwig , Bernd Freytag , Klaus Werner

The astrophysical site(s) of the r-process are uncertain, with candidates such as neutron star mergers and magneto-rotational supernovae predicting different event rates, delay times, and heavy-element yields. Galactic chemical evolution…

Astrophysics of Galaxies · Physics 2026-05-27 M. Molero , A. Arcones , F. Montes , C. J. Hansen

The stellar population in the Galactic halo is characterised by a large fraction of CEMP stars. Most CEMP stars are enriched in $s$-elements (CEMP-$s$ stars), and some of these are also enriched in $r$-elements (CEMP-$s/r$ stars). One…

Solar and Stellar Astrophysics · Physics 2015-09-02 C. Abate , O. R. Pols , R. J. Stancliffe , R. G. Izzard , A. I. Karakas , T. C. Beers , Y. S. Lee

Abundances of heavier elements (barium and beyond) in many neutron-capture-element-rich halo stars accurately replicate the solar system r-process pattern. However, abundances of lighter neutron-capture elements in these stars are not…

The origin of carbon-enhanced metal-poor (CEMP) stars plays a key role in characterising the formation and evolution of the first stars and the Galaxy since the extremely-poor (EMP) stars with [Fe/H] \leq -2.5 share the common features of…

Solar and Stellar Astrophysics · Physics 2017-03-29 Takuma Suda , Shimako Yamada , Masayuki Y. Fujimoto

Carbon-enhanced metal-poor (CEMP) stars are ancient stars enriched in carbon and heavy elements. Some of these stars exhibit enhanced s-process and/or r-process elements, hence are classified as CEMP-s, CEMP-rs, or CEMP-r. This…

Solar and Stellar Astrophysics · Physics 2025-10-16 A. M. Riyas , D. Karinkuzhi , S. Van Eck , A. Choplin , S. Goriely , L. Siess , M. V. Keerthy , A. Jorissen , T. Merle

We model the history of Galactic r-process enrichment using high-redshift, high-resolution zoom cosmological simulations of a Milky Way (MW) type halo. We assume that all r-process sources are neutron star mergers (NSMs) with a power law…

Astrophysics of Galaxies · Physics 2019-05-08 Mohammadtaher Safarzadeh , Richard Sarmento , Evan Scannapieco

We have made a parametric study of s-process nucleosynthesis in the metal poor ([Fe/H]=-2.7) stars LP625-44 and LP706-7. We find that a high neutron exposure and a small overlap factor are necessary to fit the abundance pattern observed in…

We model the evolution of the abundances of light elements in carbon-enhanced metal-poor (CEMP) stars, under the assumption that such stars are formed by mass transfer in a binary system. We have modelled the accretion of material ejected…

Astrophysics · Physics 2009-11-13 Richard J. Stancliffe

Carbon-enhanced metal-poor (CEMP) stars span a wide range of stellar populations, from bona fide second-generation stars to later forming stars that provide excellent probes of, e.g., binary mass transfer. Here we analyse 11 metal-poor…

The supernova yields of r-process elements are obtained as a function of the mass of their progenitor stars from the abundance patterns of extremely metal-poor stars on the left-side [Ba/Mg]-[Mg/H] boundary with a procedure proposed by…

Astrophysics · Physics 2008-11-26 Zhe Chen , Jiang Zhang , YanPing Chen , WenYuan Cui , Bo Zhang

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…

Depending on mass and metallicity as well as evolutionary phase, stars occasionally experience convective-reactive nucleosynthesis episodes. We specifically investigate the situation when nucleosynthetically unprocessed, H-rich material is…

Intermediate mass stellar evolution tracks from the main sequence to the tip of the AGB for five initial masses (2 to 6Msun) and metallicity Z=0.0001 have been computed. The detailed 1D structure and evolution models include exponential…

Astrophysics · Physics 2016-08-30 Falk Herwig