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Related papers: The Shards of $\omega$ Centauri

200 papers

We applied Stars' Galactic Origin (StarGO) algorithm in 7D space (i.e., [Fe/H], [Mg/Fe], [Al/Fe], $L_{z}$, $J_{r}$, $J_{z}$, $E$) to analyze stars in the inner halo with APOGEE DR17. We identified some known substructures, including…

Astrophysics of Galaxies · Physics 2025-04-03 Zhongcheng Li , Cuihua Du , Haoyang Liu , Dashuang Ye

We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that…

We have performed the largest ever particle simulation of a Milky Way-sized dark matter halo, and present the most comprehensive convergence study for an individual dark matter halo carried out thus far. We have also simulated a sample of 6…

We use the distribution of accreted stars in SDSS-Gaia DR2 to demonstrate that a non-trivial fraction of the dark matter halo within Galactocentric radii of 7.5-10 kpc and $|z| > 2.5$ kpc is in substructure, and thus may not be in…

Astrophysics of Galaxies · Physics 2019-07-31 Lina Necib , Mariangela Lisanti , Vasily Belokurov

The local stellar halo of the Milky Way is known to contain the debris from accreted dwarf galaxies and globular clusters, in the form of stellar streams and over-densities in the space of orbital properties (e.g. integrals of motion).…

In this second installment of the series, we look at the internal kinematics of the multiple stellar populations of the globular cluster $\omega$ Centauri in one of the parallel Hubble Space Telescope (HST) fields, located at about 3.5…

We improve the identification and isolation of individual stellar populations in the Galactic halo based on an updated set of empirically calibrated stellar isochrones in the Sloan Digital Sky Survey (SDSS) and Pan-STARRS 1 (PS1)…

Astrophysics of Galaxies · Physics 2021-02-10 Deokkeun An , Timothy C. Beers

There are expected to be physical relationships between the globular clusters (GCs) and stellar substructures in the Milky Way, not all of which have yet been found. We search for such substructures from a combined halo sample of SDSS blue…

Astrophysics of Galaxies · Physics 2020-08-05 Zhen Yuan , Jiang Chang , Timothy C. Beers , Yang Huang

Recent studies suggest that chemical abundances hold the key to disentangling halo substructure, providing a more reliable tracer than dynamics alone. We aim to probe the Milky Way stellar halo using high-dimensional chemical abundances…

Astrophysics of Galaxies · Physics 2026-04-08 Milan Quandt-Rodriguez , Sara Lucatello , Lorenzo Spina , Mario Pasquato , Marco Canducci

A small fraction of the halo field is made up of stars that share the light element (Z<=13) anomalies characteristic of second generation globular cluster (GC) stars. The ejected stars shed light on the formation of the Galactic halo by…

Relics of ancient accretion events experienced by the Milky Way are predominantly located within the stellar halo of our Galaxy. However, debris from different objects display overlapping distributions in dynamical spaces, making it…

Astrophysics of Galaxies · Physics 2024-01-10 E. Ceccarelli , D. Massari , A. Mucciarelli , M. Bellazzini , A. Nunnari , F. Cusano , C. Lardo , D. Romano , I. Ilyin , A. Stokholm

We present an analysis of Galactic halo structure and substructure traced by ~500 RR Lyrae stars in the SDSS stripe 82 region. The main result of this study is a 2D map of the Galactic halo that reaches distances of 100 kpc and traces…

Astrophysics of Galaxies · Physics 2011-05-23 Branimir Sesar

[ABRIDGED] $\omega$ Centauri (NGC 5139) contains large numbers of variable stars of different types and, in particular, more than a hundred RR Lyrae stars. We have conducted a variability survey of $\omega$ Cen in the NIR, using ESO's 4.1m…

Solar and Stellar Astrophysics · Physics 2015-05-13 C. Navarrete , R. Contreras Ramos , M. Catelan , C. M. Clement , F. Gran , J. Alonso-García , R. Angeloni , M. Hempel , I. Dékány , D. Minniti

We present an analysis of the spatial and chemical sub-structures in a remote halo field in the nearby giant elliptical galaxy Centaurus A (NGC~5128), situated at about 38 kpc from the centre of the galaxy. The observations were taken with…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 M. Mouhcine , R. Ibata , M. Rejkuba

We apply the clustering algorithm HDBSCAN on the Gaia early third data release astrometry combined with the Gaia second data release radial velocity measurements of almost 5.5 million stars to identify the local stellar kinematic…

Astrophysics of Galaxies · Physics 2023-03-15 Xiaowei Ou , Lina Necib , Anna Frebel

Based on the second Gaia data release (Gaia DR2) and spectroscopy from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Data, we identified 20,089 halo stars kinematically and chemically. The halo streams in the solar…

Astrophysics of Galaxies · Physics 2019-04-03 Hefan Li , Cuihua Du , Shuai Liu , Thomas Donlon , Heidi Jo Newberg

We present chemodynamical links between the present-day Milky Way halo field star population and Galactic globular clusters (GCs) using a dataset that combines information from the $\rm{\it Gaia}$ space mission and the Sloan Digital Sky…

Astrophysics of Galaxies · Physics 2020-05-27 Michael Hanke , Andreas Koch , Zdenek Prudil , Eva K. Grebel , Ulrich Bastian

Modern theories of galaxy formation predict that the Galactic stellar halo was hierarchically assembled from the accretion and disruption of smaller systems. This hierarchical assembly is expected to produce a high degree of structure in…

We have determined stellar parameters and abundances for 221 giant branch stars in the globular cluster {\omega} Centauri. A combination of photometry and lower-resolution spectroscopy was used to determine temperature, gravity,…

Solar and Stellar Astrophysics · Physics 2015-06-11 Jeffrey D. Simpson , P. L. Cottrell , C. C. Worley