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Related papers: The Kapteyn moving group is not tidal debris from …

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Using kinematics from Gaia and the large elemental abundance space of the second data release of the GALAH survey, we identify two new members of the Fimbulthul stellar stream, and chemically tag them to massive, multi-metallic globular…

We present manganese abundances in 10 red-giant members of the globular cluster Omega Centauri; 8 stars are from the most metal-poor population (RGB MP and RGB MInt1) while two targets are members of the more metal rich groups (RGB MInt2…

Astrophysics of Galaxies · Physics 2015-05-19 Katia Cunha , Verne V. Smith , Maria Bergemann , Nicholas B. Suntzeff , David L. Lambert

We present radial velocities, Fe, and Al abundances for 180 red giant branch (RGB) stars in the Galactic globular cluster Omega Centauri ($\omega$ Cen). The majority of our data lie in the range 11.0$<$V$<$13.5, which covers the RGB from…

Multiple populations have been detected in several globular clusters (GC) that do not display a spread in metallicity. Unusual features of their CMD can be interpreted in terms of differences in the Helium content of the stars belonging to…

Solar and Stellar Astrophysics · Physics 2015-05-28 L. Pasquini , P. Mauas , H. U. Kaufl , C. Cacciari

We present abundances of several light, alpha, Fe-peak, and neutron-capture elements for 66 red giant branch (RGB) stars in the Galactic globular cluster Omega Centauri. Our observations lie in the range 12.0<V<13.5 and focus on the…

Solar and Stellar Astrophysics · Physics 2011-02-11 Christian I. Johnson , Catherine A. Pilachowski , R. Michael Rich , Jon P. Fulbright

Globular clusters (GCs) are important donors to the build-up of the Milky Way (MW) stellar halo, having contributed at the ten percent level over the Galactic history. Stars that originated from the second generation of dissolved or…

While most moving groups are young and nearby, a small number have been identified in the Galactic halo. Understanding the origin and evolution of these groups is an important piece of reconstructing the formation history of the halo. Here…

Astrophysics of Galaxies · Physics 2021-08-25 S. C. Schuler , J. J. Andrews , V. R. Clanzy , M. Mourabit , J. Chanamé , M. A. Agüeros

Omega Centauri is no longer the only globular cluster known to contain multiple stellar populations, yet it remains the most puzzling. Due to the extreme way in which the multiple stellar population phenomenon manifests in this cluster, it…

Using the 2dF multi-fibre instrument on the AAT, moderate resolution spectra have been obtained for a large sample of stars on the main sequence and at the turnoff in the unusual globular cluster omega Centauri. We investigate the behaviour…

Astrophysics · Physics 2009-11-11 G. S. Da Costa , Laura Stanford , John E. Norris , R. D. Cannon

Omega Cen is composed of several stellar populations. Their history might allow us to reconstruct the evolution of this complex object. We performed a statistical cluster analysis on the large data set provided by Johnson and Pilachowski…

Astrophysics of Galaxies · Physics 2015-05-28 Raffaele Gratton , Christian I. Johnson , Sara Lucatello , Valentina D'Orazi , Catherine A. Pilachowski

The blue Main Sequence (bMS) of $\omega$ Cen implies a ratio of helium to metal enrichment $\Delta Y/\Delta Z \approx 70$, which is a major enigma. We show that rotating models of low metallicity stars, which account for the anomalous…

Astrophysics · Physics 2009-11-11 André Maeder , Georges Meynet

High spectral resolution and high signal-to-noise ratio optical spectra of red giants in the globular cluster Omega Centauri are analysed for stellar parameters and chemical abundances of 15 elements including helium by either line…

Solar and Stellar Astrophysics · Physics 2020-05-20 Arumalla B. S. Reddy

Recent dynamical analysis based on Gaia data have revealed major accretion events in Milky Way's history. Nevertheless, our understanding of the primordial Galaxy is hindered because the bona fide identification of the most metal-poor and…

\omega}Centauri ({\omega}Cen) is the most enigmatic Galactic globular cluster (GC), with unmatched chemical complexity. We combine photometric and spectroscopic catalogs to identify its distinct stellar populations and to investigate their…

NGC3201 is a globular cluster (GC) which shows very peculiar kinematic characteristics including an extreme radial velocity and a highly retrograde orbit, strongly suggesting an extraGalactic origin. Our aims are to study NGC3201 in the…

Astrophysics of Galaxies · Physics 2015-06-15 C. Muñoz , D. Geisler , S. Villanova

Context. Omega Cen is the largest known globular cluster in the Milky Way. It is also quite a complex object with a large metallicity spread and multiple stellar populations. Despite a number of studies over the past several decades, the…

Astrophysics of Galaxies · Physics 2025-04-23 Nagaraj Vernekar , Sara Lucatello , Pete Kuzma , Lorenzo Spina

The peripheral regions of globular clusters (GCs) are extremely challenging to study due to their low surface brightness nature and the dominance of Milky Way contaminant populations along their sightlines. We have developed a probabilistic…

Astrophysics of Galaxies · Physics 2021-08-18 Pete B. Kuzma , Annette M. N. Ferguson , Jorge Peñarrubia

We present the results of a detailed NLTE abundance study of nine beta Cephei stars, all of them being prime targets for theoretical modelling: gamma Peg, delta Cet, nu Eri, beta CMa, xi1 CMa, V836 Cen, V2052 Oph, beta Cep and DD (12) Lac.…

Astrophysics · Physics 2009-11-11 T. Morel , K. Butler , C. Aerts , C. Neiner , M. Briquet

The origins of most stellar streams in the Milky Way are unknown. With improved proper motions provided by Gaia EDR3, we show that the orbits of 23 Galactic stellar streams are highly clustered in orbital phase space. Based on their…

Stellar streams in the Galactic halo are useful probes of the assembly of galaxies like the Milky Way. Many tidal stellar streams that have been found in recent years are accompanied by a known progenitor globular cluster or dwarf galaxy.…