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Related papers: R-process-rich stellar streams in the Milky Way

200 papers

We study the dynamics of faint stellar substructures around the Umbrella Galaxy, NGC 4651, which hosts a dramatic system of streams and shells formed through the tidal disruption of a nucleated dwarf elliptical galaxy. We elucidate the…

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…

Rapid neutron-capture (i.e., r-process) nucleosynthesis calculations, employing internally consistent and physically realistic nuclear physics input (QRPA beta-decay rates and the ETFSI-Q nuclear mass model), have been made. These…

The origin of a new kinematically identified metal-poor stellar stream, the KFR08 stream, has not been established. We present stellar parameters, stellar ages, and detailed elemental abundances for Na, Mg, Al, Si, Ca, Sc, Ti, Cr, Ni, Zn,…

Solar and Stellar Astrophysics · Physics 2015-08-19 C. Liu , S. Feltzing , G. Ruchti

We use cosmological, magnetohydrodynamical simulations of Milky Way-mass galaxies from the Auriga project to study their enrichment with rapid neutron capture (r-process) elements. We implement a variety of enrichment models from both…

By adopting a chemical evolution model for the Milky Way already reproducing the evolution of several chemical elements, we compare our theoretical results with accurate and new stellar data of neutron capture elements and we are able to…

Astrophysics · Physics 2007-08-31 Gabriele Cescutti

Ground- and space-based observations of stellar heavy element abundances are providing a clearer picture of the chemical evolution of the Galaxy. A large number of (r)apid and (s)low neutron capture process elements, including the first…

Astrophysics · Physics 2007-05-23 John J Cowan , Christopher Sneden , James W Truran , Debra L Burris

Neutron-capture elements, those with Z > 35, are the least well-understood in terms of nucleosynthesis and formation environments. The rapid neutron-capture, or r-process, elements are formed in the environments and/or remnants of massive…

Solar and Stellar Astrophysics · Physics 2016-06-22 Jamie C. Overbeek , Eileen D. Friel , Heather R. Jacobson

Milky Way halo substructures identified in dynamical space are known to suffer from contamination from the Milky Way in-situ stars, which makes their accreted origins uncertain. We present detailed chemical abundances of 35 stars belonging…

We investigate whether the anomalous elemental abundance patterns in some of the C-enhanced metal-poor-s+r (CEMP-r/s) stars are consistent with predictions of nucleosynthesis yields from the i-process, a neutron-capture regime at neutron…

Solar and Stellar Astrophysics · Physics 2015-07-28 L. Dardelet , C. Ritter , P. Prado , E. Heringer , C. Higgs , S. Sandalski , S. Jones , P. Denissenkov , K. Venn , M. Bertolli , M. Pignatari , P. Woodward , F. Herwig

We report the first detection of elements at all three r-process peaks in the metal-poor halo star HD 160617. These elements include arsenic and selenium, which have not been detected previously in halo stars, and the elements tellurium,…

Solar and Stellar Astrophysics · Physics 2012-04-19 Ian U. Roederer , James E. Lawler

The Milky Way halo was predominantly formed by the merging of numerous progenitor galaxies. However, our knowledge of this process is still incomplete, especially in regard to the total number of mergers, their global dynamical properties…

Chemical abundances of stars in the Milky Way disk are empirical tracers of its enrichment history. However, they capture joint-information that is valuable to disentangle. In this work, we seek to quantify how individual abundances evolve…

Astrophysics of Galaxies · Physics 2023-02-08 Bridget Ratcliffe , Melissa Ness

We investigate the production sites and the enrichment history of $r$-process elements in the Galaxy, as traced by the [Eu/Fe] ratio, using the high resolution, cosmological zoom-in simulation `Eris'. At $z=0$, Eris represents a close…

Astrophysics of Galaxies · Physics 2015-07-15 Sijing Shen , Ryan Cooke , Enrico Ramirez-Ruiz , Piero Madau , Lucio Mayer , Javiera Guedes

The chemical abundances of metal-poor stars provide important clues to explore stellar formation history and set significant constraints on models of the r-process. In this work, we find that the abundance patterns of the light and iron…

Solar and Stellar Astrophysics · Physics 2014-07-21 Hongjie Li , Wenjuan Ma , Wenyuan Cui , Bo Zhang

An important step in understanding the formation and evolution of the Nuclear Star Cluster (NSC) is to investigate its chemistry and chemical evolution. Additionally, exploring the relationship of the NSC to the other structures in the…

Astrophysics of Galaxies · Physics 2025-02-26 Govind Nandakumar , Nils Ryde , Mathias Schultheis , R. Michael Rich , Paola Di Matteo , Brian Thorsbro , Gregory Mace

We explore the origins of the young B-type stars found by Casetti-Dinescu et al.(2014) at the outskirts of the Milky-Way disk in the sky region of Leading Arm of the Magellanic Stream. High-resolution spectroscopic observations made with…

We present the chemical composition of 206 red giant branch stars members of the Small Magellanic Cloud (SMC) using optical, high-resolution spectra collected with the multi-object spectrograph FLAMES-GIRAFFE at the ESO Very Large…

Astrophysics of Galaxies · Physics 2023-03-29 A. Mucciarelli , A. Minelli , M. Bellazzini , C. Lardo , D. Romano , L. Origlia , F. R. Ferraro

Cold stellar streams---produced by tidal disruptions of clusters---are long-lived, coherent dynamical features in the halo of the Milky Way. Due to their different ages and different positions in phase space, different streams tell us…

Astrophysics of Galaxies · Physics 2018-11-14 Ana Bonaca , David W. Hogg

We report the kinematic, orbital, and chemical properties of 12 stellar streams with no evident progenitors, using line-of-sight velocities and metallicities from the Southern Stellar Stream Spectroscopic Survey ($S^5$), proper motions from…