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

collaborators

32 papers

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.SR2025

Detailed Chemical Abundance Analysis of the Brightest Stars in the Turranburra and Willka Yaku Stellar Streams

Kaitlin B. Webber, Terese T. Hansen, Jennifer L. Marshall +20

We present a detailed chemical abundance analysis of the three brightest known stars from each of the Turranburra and Willka Yaku stellar streams using high-resolution Magellan/MIK…

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.IM2024

Do SETI Optimists Have a Fine-Tuning Problem?

David Kipping, Geraint Lewis

In ecological systems, be it a petri dish or a galaxy, populations evolve from some initial value (say zero) up to a steady state equilibrium, when the mean number of births and de…

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.SR2024

The Gasing Pangkah Collaboration: I. Asteroseismic Identification and Characterisation of a Rapidly-Rotating Engulfment Candidate

J. M. Joel Ong, Marc Teng Yen Hon, Melinda Soares-Furtado +19

We report the discovery and characterisation of TIC 350842552 ("Zvrk"), an apparently isolated, rapidly-rotating () red giant observed by TESS in…

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…