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Related papers: r-process Abundance Patterns in the Globular Clust…

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Recent theoretical yields and chemical evolution models demonstrate that intermediate-mass AGB stars cannot reproduce the observed abundance distributions of O, Na, Mg, and Al. As a further observational test of this finding, we present…

Abundance observations indicate the presence of rapid-neutron capture (i.e., r-process) elements in old Galactic halo and globular cluster stars. Recent observations of the r-process-enriched star BD +17 3248 include new abundance…

Solar and Stellar Astrophysics · Physics 2011-06-07 John J. Cowan , Ian U. Roederer , Christopher Sneden , James E. Lawler

Understanding the abundance pattern of metal-poor stars and the production of heavy elements through various nucleosynthesis processes offers crucial insights into the chemical evolution of the Milky Way, revealing primary sites and major…

Abundance observations indicate the presence of often surprisingly large amounts of neutron capture (i.e., s- and r-process) elements in old Galactic halo and globular cluster stars. These observations provide insight into the nature of the…

We study turbulent gas diffusion affects on $r$-process abundances in Milky Way stars, by a combination of an analytical approach and a Monte Carlo simulation. Higher $r$-process event rates and faster diffusion, lead to more efficient…

High Energy Astrophysical Phenomena · Physics 2020-06-24 Paz Beniamini , Kenta Hotokezaka

We study the enrichment of the interstellar medium with rapid neutron capture (r-process) elements produced in binary neutron star (BNS) mergers. We use a semi-analytic model to describe galactic evolution, with merger rates and time delay…

High Energy Astrophysical Phenomena · Physics 2021-08-11 Irina Dvorkin , Frédéric Daigne , Stéphane Goriely , Elisabeth Vangioni , Joseph Silk

The production of elements by rapid neutron capture (r-process) in neutron-star mergers is expected theoretically and is supported by multimessenger observations of gravitational-wave event GW170817: this production route is in principle…

High Energy Astrophysical Phenomena · Physics 2020-08-17 Daniel M. Siegel , Jennifer Barnes , Brian D. Metzger

The very metal-poor star HE 0338-3945 shows a double-enhanced pattern of the neutron-capture elements. The study to this sample could make people gain a better understanding of s- and r-process nucleosynthesis at low metallicity. Using a…

Solar and Stellar Astrophysics · Physics 2010-10-22 Wenyuan Cui , Jiang Zhang , Zizhong Zhu , Bo Zhang

The existence of neutron star mergers has been supported since the discovery of the binary pulsar and the observation of its orbital energy loss, consistent with General Relativity. They are considered nucleosynthesis sites of the rapid…

High Energy Astrophysical Phenomena · Physics 2017-10-09 F. -K. Thielemann , M. Eichler , I. V. Panov , B. Wehmeyer

We have carried out a detailed abundance analysis for 21 elements in a sample of 25 stars with a wide range in luminosity from luminous giants to stars near the main sequence turnoff in the globular cluster M13 and in a sample of 13 stars…

Astrophysics · Physics 2009-10-12 Judith G. Cohen , Jorge Melendez

Globular clusters (GCs) are key to understanding the formation and evolution of our Galaxy. While the abundances of light and Fe-peak elements in GCs have been widely studied, investigations into heavier, neutron-capture elements -- and…

Accurate relative abundances have been obtained for a sample of 21 mildly metal-poor stars from the analysis of high resolution and high signal-to-noise spectra. With these accurate results, correlations between relative abundances have…

Astrophysics · Physics 2007-05-23 E. Jehin , P. Magain , C. Neuforge , A. Noels , G. Parmentier , A. Thoul

The chemical abundances of elements such as barium and the lanthanides are essential to understand the nucleosynthesis of heavy elements in the early Universe as well as the contribution of different neutron capture processes (for example…

In a brief review of abundances neutron-capture elements (Z > ~30) in metal-poor halo stars, attention is called to their star-to-star scatter, the dominance of r-process synthesis at lowest metallicities, the puzzle of the lighter members…

Astrophysics · Physics 2016-11-03 C. Sneden , J. J. Cowan , J. W. Truran

Carbon-enhanced metal-poor (CEMP) stars in the Galactic Halo display enrichments in heavy elements associated with either the s (slow) or the r (rapid) neutron-capture process (e.g., barium and europium respectively), and in some cases they…

Solar and Stellar Astrophysics · Physics 2016-11-15 Melanie Hampel , Richard J. Stancliffe , Maria Lugaro , Bradley S. Meyer

The rapid neutron-capture process or r-process is thought to produce the majority of the heavy elements (Z > 30) in extremely metal-poor stars. The same process is also responsible for a significant fraction of the heavy elements in the…

Solar and Stellar Astrophysics · Physics 2017-12-13 Andrew R. Casey , Kevin C. Schlaufman

Extensive progress has been recently made into our understanding of heavy element production via the $r$-process in the Universe, specifically with the first observed neutron star binary merger (NSBM) event associated with the gravitational…

We have used spectra obtained as part of the Science Verification program of the FLAMES multi-object spectrograph mounted on Kueyen (VLT-UT2) to perform an abundance analysis of stars along the giant branch (RGB) in the globular cluster NGC…

Astrophysics · Physics 2009-11-10 Eugenio Carretta , Angela Bragaglia , Carla Cacciari , Emanuel Rossetti

Recent observations of heavy elements produced by rapid neutron capture (r-process) in the halo have shown a striking and unexpected behavior: within a single star, the relative abundances of r-process elements heavier than Eu are the same…

Astrophysics · Physics 2009-11-06 Brian D. Fields , James W. Truran , John J. Cowan

Some recent observations of the abundances of s-process, r-process, and alpha elements in metal-poor stars have led to a new scenario for their formation. According to this scenario, these stars were born in a globular cluster and accreted…

Astrophysics · Physics 2009-11-07 A. Thoul , A. Jorissen , S. Goriely , E. Jehin , P. Magain , A. Noels , G. Parmentier