activity
20032026
most citedThe Great Escape: Discovery of a nearby 1700 km/s star ejected from the Milky Way by Sgr A*

133 citations · 500 across the 30 of their papers we have counts for

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Showing astro-ph.GAShow all

27 papers · 1 filter

astro-ph.GA2026

Boötes III is a Tidally Disrupting Ultra-Faint Dwarf Galaxy on an Eccentric Polar Orbit

Ting S. Li, Denis Erkal, Andrew B. Pace +20

We present updated systemic properties of the ultra-faint dwarf galaxy Boötes III from the Southern Stellar Stream Spectroscopic Survey (S). We identify 21 high-probability mem…

astro-ph.GA2026

The GALAH Survey: Neutron-Capture Elemental Abundances for 350,000 Gaia-RVS spectra and the Chemodynamics of Accreted Structures

Pradosh Barun Das, Daniel B. Zucker, Aldo Mura-Guzmán +15

We present a comprehensive data-driven spectroscopic analysis of 357,415 red giant stars using Gaia DR3 Radial Velocity Spectrometer (RVS) spectra (8460-8700 A; ),…

astro-ph.GA2026

The DECam MAGIC Survey: Investigating the Jet Stellar Stream with Photometric Metallicities

H. Q. Do, A. Chiti, P. S. Ferguson +27

Stellar streams are dynamically fragile structures formed by the tidal disruption of dwarf galaxies and stellar clusters. These objects are valuable tracers of the gravitational po…

astro-ph.GA2026

Epicyclic Density Variations in the Indus Stellar Stream

Yong Yang, Geraint F. Lewis, Ting S. Li +12

Longitudinal density fluctuations observed in stellar streams can result from gravitational interactions with massive perturbers in the Milky Way, such as dark matter subhalos. Ana…

astro-ph.GA2026

Searching for and characterizing halo substructures with the GALAH DR4 survey

Iryna Kushniruk, Kristopher Youakim, Karin Lind +12

Recent studies show that the Milky Way stellar halo is composed of populations of different origins, shaped by multiple accretion events. To better understand the formation of the…

astro-ph.GA2026

Rotational Kinematics in the Globular Cluster System of M31: Insights from Bayesian Inference

Yuan Li, Brendon J. Brewer, Geraint F. Lewis +1

As ancient stellar systems, globular clusters (GCs) offer valuable insights into the dynamical histories of large galaxies. Previous studies of GC populations in the inner and oute…

astro-ph.GA2025

: Tidal Disruption in Crater 2 and Formation of Diffuse Dwarf Galaxies in the Local Group

Guilherme Limberg, Alexander P. Ji, Ting S. Li +19

We present results of a spectroscopic campaign around the diffuse dwarf galaxy Crater 2 (Cra2) and its tidal tails as part of the Southern Stellar Stream Spectroscopic Survey ($S^5…

astro-ph.GA2025

Unveiling M33's Hidden Merger History: A Potential Population of Star Clusters on Retrograde Orbits

Borja Anguiano, Geraint F. Lewis, Steven R. Majewski

We report the discovery of a possible sub-population of stellar clusters that appear to follow retrograde orbits around the third largest galaxy in the Local Group, M33 (Triangulum…

astro-ph.GA2025

Accreted Globular Clusters and Horizontal Branch Morphology in the Outer Halo of M31

Gracie McGill, Annette M. N. Ferguson, Dougal Mackey +7

M31 hosts a rich population of outer halo ( kpc) globular clusters (GCs), many of which show strong evidence for spatial and/or kinematical associations with la…

astro-ph.GA2025★ 1 cited

Sifting for a Stream: The Morphology of the Stellar Stream

Benjamin Cohen, Alexander P. Ji, Peter S. Ferguson +18

Stellar streams are sensitive laboratories for understanding the small-scale structure in our Galaxy's gravitational field. Here, we analyze the morphology of the stellar st…

astro-ph.GA2025★ 7 cited

Flipping of the tidal tails of the Ophiuchus stream due to the decelerating Galactic bar

Yong Yang, Geraint F. Lewis, Denis Erkal +16

The Ophiuchus stellar stream presents a puzzle due to its complicated morphology, with a substructure perpendicular to the main track (spur), a broadened tail (fanning), and a shor…

astro-ph.GA2025★ 5 cited

The GALAH survey: Improving chemical abundances using star clusters

Janez Kos, Sven Buder, Kevin L. Beeson +18

Large spectroscopic surveys aim to consistently compute stellar parameters of very diverse stars while minimizing systematic errors. We explore the use of stellar clusters as bench…

astro-ph.GA2025

The Hubble Space Telescope Survey of M31 Satellite Galaxies IV. Survey Overview and Lifetime Star Formation Histories

A. Savino, D. R. Weisz, A. E. Dolphin +35

From orbits of HST imaging, we present deep homogeneous resolved star color-magnitude diagrams that reach the oldest main sequence turnoff and uniformly measured star forma…

astro-ph.GA2024★ 11 cited

: New insights from deep spectroscopic observations of the tidal tails of the globular clusters NGC 1261 and NGC 1904

Petra Awad, Ting S. Li, Denis Erkal +22

As globular clusters (GCs) orbit the Milky Way, their stars are tidally stripped forming tidal tails that follow the orbit of the clusters around the Galaxy. The morphology of thes…

astro-ph.GA2024★ 3 cited

Chemical Abundances in the Leiptr Stellar Stream: A Disrupted Ultra-faint Dwarf Galaxy?

Kaia R. Atzberger, Sam A. Usman, Alexander P. Ji +11

Chemical abundances of stellar streams can be used to determine the nature of a stream's progenitor. Here we study the progenitor of the recently discovered Leiptr stellar stream,…

astro-ph.GA2024★ 8 cited

The GALAH Survey: Stellar parameters and abundances for 800,000 Gaia RVS spectra using GALAH DR4 and The Cannon

Pradosh Barun Das, Daniel B. Zucker, Gayandhi M. De Silva +15

Analysing stellar parameters and abundances from nearly one million Gaia Data Release 3 (DR3) Radial Velocity Spectrometer (RVS) spectra poses challenges due to the limited spectra…

astro-ph.GA2024★ 20 cited

The GALAH survey: Tracing the Milky Way's formation and evolution through RR Lyrae stars

Valentina D'Orazi, Nicholas Storm, Andrew R. Casey +39

Stellar mergers and accretion events have been crucial in shaping the evolution of the Milky Way (MW). These events have been dynamically identified and chemically characterised us…

astro-ph.GA2024★ 2 cited

Inferring dark matter subhalo properties from simulated subhalo-stream encounters

Tariq Hilmi, Denis Erkal, Sergey E. Koposov +9

In the cold dark matter paradigm, our Galaxy is predicted to contain >10000 dark matter subhaloes in the range which should be completely devoid of stars. Stella…

astro-ph.GA2024

The GALAH survey: Elemental abundances in open clusters using joint effective temperature and surface gravity photometric priors

Kevin L. Beeson, Janez Kos, Richard de Grijs +10

The ability to measure precise and accurate stellar effective temperatures () and surface gravities () is essential in determining accurate and precise abund…

astro-ph.GA2024★ 1 cited

The Power of High Precision Broadband Photometry: Tracing the Milky Way Density Profile with Blue Horizontal Branch stars in the Dark Energy Survey

Fengqing Yu, Ting S. Li, Joshua S. Speagle +9

Blue Horizontal Branch (BHB) stars, excellent distant tracers for probing the Milky Way's halo density profile, are distinguished in the vs color space from ano…

astro-ph.GA2024

Multiple Populations and a CH Star Found in the 300S Globular Cluster Stellar Stream

Sam A. Usman, Alexander P. Ji, Ting S. Li +14

Milky Way globular clusters (GCs) display chemical enrichment in a phenomenon called multiple stellar populations (MSPs). While the enrichment mechanism is not fully understood, th…

astro-ph.GA2023★ 1 cited

The Pristine Inner Galaxy Survey (PIGS) VIII: Characterising the orbital properties of the ancient, very metal-poor inner Milky Way

Anke Ardern-Arentsen, Giacomo Monari, Anna B. A. Queiroz +19

The oldest stars in the Milky Way (born in the first few billion years) are expected to have a high density in the inner few kpc, spatially overlapping with the Galactic bulge. We…

astro-ph.GA2023

The Hubble Space Telescope Survey of M31 Satellite Galaxies. III. Calibrating the Horizontal Branch as an Age Indicator for Nearby Galaxies

Connor Jennings, Alessandro Savino, Daniel Weisz +14

We present a new method for measuring the mean age of old/intermediate stellar populations in resolved, metal-poor () galaxies using only th…

astro-ph.GA2023★ 4 cited

The origin of the metallicity distributions of the NE and W stellar shelves in the Andromeda Galaxy

Stanislav Milošević, Miroslav Mićić, Geraint F. Lewis

Tidal streams and stellar shells are naturally formed in galaxy interactions and mergers. The Giant Stellar Stream (GSS), the North-East (NE), and Western (W) stellar shelves obser…