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Related papers: Neutron-Capture Element Trends in the Halo

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New elemental abundances for the neutron-capture elements Sr, Nb, Mo, Ru, La, Sm, and Eu are presented for a large sample of 180 barium (Ba) giant stars, a class of chemically peculiar objects that exhibit in their spectra enhancements of…

Solar and Stellar Astrophysics · Physics 2021-08-19 M. P. Roriz , M. Lugaro , C. B. Pereira , C. Sneden , S. Junqueira , A. I. Karakas , N. A. Drake

Dark matter particles will be captured in neutron stars if they undergo scattering interactions with nucleons or leptons. These collisions transfer the dark matter kinetic energy to the star, resulting in appreciable heating that is…

High Energy Physics - Phenomenology · Physics 2019-07-02 Nicole F. Bell , Giorgio Busoni , Sandra Robles

We present a study of neutron-capture element abundances (Sr, Y, Zr, Ba, La, Ce, Nd, Pr, and Eu) in a large and homogeneous sample of 160 F-, G-, and K-type planet-host stars located in the northern hemisphere, including 32 stars in…

Solar and Stellar Astrophysics · Physics 2025-08-14 A. Sharma , E. Stonkutė , A. Drazdauskas , R. Minkevičiūtė , Š. Mikolaitis , G. Tautvaišienė , U. Jonauskaitė

Most heavy elements beyond the iron peak are synthesized via neutron capture processes. The nature of the astrophysical sites of neutron capture processes is still very unclear. In this work we explore the observational constraints of the…

Solar and Stellar Astrophysics · Physics 2023-09-25 Jianhui Lian , Nicholas Storm , Guillaume Guiglion , Aldo Serenelli , Benoit Cote , Amanda I. Karakas , Nick Boardman , Maria Bergemann

Thanks to the large amount of spectroscopic and photometric data assembled in the last couple of decades, the assumption that all globular clusters (GCs) contain a simple mono-metallic stellar population has been modified. Besides the…

Solar and Stellar Astrophysics · Physics 2013-02-12 A. F. Marino

We investigate the origin of the abundance ratios and scatter of the neutron-capture elements Sr, Ba and Eu in the stellar halo of a Milky Way-mass galaxy formed in a hydrodynamical cosmological simulation, and compare them with those of…

Astrophysics of Galaxies · Physics 2022-09-21 Cecilia Scannapieco , Gabriele Cescutti , Cristina Chiappini

We present CN and CH indices and CaII triplet metallicities for 34 giant stars and chemical abundances for 33 elements in 14 giants in the globular cluster M2. Assuming the program stars are cluster members, our analysis reveals (i) an…

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

It is well-established that the vast majority of metal-poor Galactic halo stars shows evidence for enrichment by solely massive stars. Recent observations have identified more varied behavior in the pattern of elemental abundances measured…

Astrophysics · Physics 2016-08-30 Gerard Gilmore , Rosemary F. G. Wyse

Abundance ratios of radioactive to stable neutron-capture elements in very metal-poor stars may be used to estimate the age of our Galaxy. But extracting accurate ages from these data requires continuing work on many fronts: a)…

Astrophysics · Physics 2007-05-23 C. Sneden

Many works have attempted to investigate the astrophysical origin of the neutron-capture elements in the metalpoor star HD 140283. However, no definite conclusions have been drawn. In this work, using the abundancedecomposed approach, we…

Solar and Stellar Astrophysics · Physics 2015-11-17 Ping Niu , Wenyuan Cui , Bo Zhang

All the elements heavier than Fe are produced either by slow (-s) or rapid (-r) neutron-capture process. Neutron density prevailing in the stellar sites is one of the major factors that determines the type of neutron-capture processes. We…

Solar and Stellar Astrophysics · Physics 2021-01-29 Meenakshi Purandardas , Aruna Goswami

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

Whereas light element abundance variations are a hallmark of globular clusters, there is little evidence for variation in neutron-capture elements. A significant exception is M15, which shows a star-to-star dispersion in neutron-capture…

Solar and Stellar Astrophysics · Physics 2023-11-17 Evan N. Kirby , Alexander P. Ji , Mikhail Kovalev

The production of about half of the heavy elements found in nature is assigned to a specific astrophysical nucleosynthesis process: the rapid neutron capture process (r-process). Although this idea has been postulated more than six decades…

We present a chemical composition analysis of 36 giant stars in mildly metal-poor globular cluster M5. In comparing the M5 results to those obtained in M4, a cluster previously considered to be a ``twin'' in age, metallicity and chemical…

The slow ($s$) and intermediate ($i$) neutron ($n$) capture processes occur both in asymptotic giant branch (AGB) stars, and in massive stars. To study the build-up of the $s$- and $i$-products at low metallicity, we investigate the…

We present a comprehensive abundance analysis of 20 elements for 16 new low-metallicity stars from the Chemical Abundances of Stars in the Halo (CASH) project. The abundances have been derived from both Hobby-Eberly Telescope High…

Context. Thanks to the heroic observational campaigns carried out in recent years we now have large samples of metal-poor stars for which measurements of detailed abundances exist. [...] These data hold important clues on the nature of the…

Astrophysics of Galaxies · Physics 2014-05-08 Gabriele Cescutti , Cristina Chiappini

Compact binary mergers involving at least one neutron star are promising sites for the synthesis of $\textit{r}$-process elements found in stars and planets. However, mergers can take place at significant offsets from their host galaxies,…

Astrophysics of Galaxies · Physics 2022-11-09 Benjamin Amend , Jonathan Zrake , Dieter H. Hartmann
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