activity
20192026
most citedTwo Ultra-Faint Milky Way Stellar Systems Discovered in Early Data from the DECam Local Volume Exploration Survey

95 citations · 149 across the 25 of their papers we have counts for

collaborators

29 papers

astro-ph.GA2026

Hidden Disruption in Milky Way-like Satellite Galaxy Populations

Gray Thoron, Nora Shipp, Alexander H. Riley +9

Determining whether a satellite galaxy is tidally disrupting from photometric observations alone remains a fundamental challenge in near-field cosmology. Cosmological simulations o…

astro-ph.GA2026

EDGE-INFERNO: The chemical signatures of assembly history in reionization fossils

Eric P. Andersson, Martin P. Rey, Alexander P. Ji +9

In galaxies, stellar populations represent a superposition of both in situ and accreted components, tracing internal chemical evolution as well as the histories of merged satellite…

astro-ph.GA2026

Discovery, Characterization, and Potential Origins of a Stream in the Stellar Halo of Nearby LMC-Mass Galaxy NGC 55

Benjamin N. Velguth, Burçin Mutlu-Pakdil, Erik Tollerud +33

We present a previously undetected stellar stream in the halo of the LMC-mass dwarf galaxy NGC 55 (2 Mpc), as part of an ongoing effort to characterize the stellar halos of LMC/SMC…

astro-ph.GA2026

Rubin Observatory Reveals a Dust-Shrouded Halo Globular Cluster in Ophiuchus

Aashay Pai, William Cerny, Andrew B. Pace +9

We present the discovery of the Milky Way satellite Rubin-GC1 (Rubin J1628-1735) using data from the NSF-DOE Vera C. Rubin Observatory's Early Data Preview 2. The system was discov…

astro-ph.SR2026

The Carbon-Dependent Binary Frequency of CEMP-no Stars

John D. Dixon, Terese T. Hansen, Jennifer Marshall +15

Studies of the oldest and most metal-poor stars in the Milky Way confirm a common chemical signature of high carbon abundances and subsolar neutron-capture enrichment. The so-calle…

astro-ph.GA2026

Deep Imaging of Grus II and Horologium II: Structure and Extent of Two Ultra-Faint Milky Way Satellites

Deepthi S. Prabhu, David J. Sand, Anirudh Chiti +29

We present deep, wide-field Magellan/Megacam imaging of the ultra-faint Milky Way (MW) satellites Grus II (Gru II) and Horologium II (Hor II), with the aim of deriving improved con…

astro-ph.GA2026

Disentangling the Distant Stellar Halo Using K-Giants in the DESI Year 3 Data

Namitha Kizhuprakkat, Andrew P. Cooper, Wenting Wang +42

We present a sample of 88,959 K-giants from DESI Milky Way Survey Year 3 data, which we use to characterize the chemo-dynamical properties of the stellar halo at Galactocentric dis…

astro-ph.GA2026

The Milky Way's Missing In-Situ Halo

Madeline Lucey, Robyn E. Sanderson, Alexander H. Riley +3

The Milky Way's stellar halo preserves a record of its mass assembly history, encoding accretion events in its structural properties. Among the most prominent of these features is…

astro-ph.GA2026

Constraining the Galactic bar using the M92 stellar stream

Amanda Byström, Sergey E. Koposov, Ting. S. Li +42

Stellar streams are excellent probes of the gravitational potential in which they evolve. In the Milky Way (MW), globular cluster (GC) streams are routinely used to infer propertie…

astro-ph.GA2026

Characterizing the GD-1 Stream with DESI DR2 Data: Thin Stream and Hot Cocoon

Emma Jarvis, Ting S. Li, Sergey E. Koposov +54

GD-1 is among the longest, coldest stellar streams in the Milky Way, making it an ideal target for probing dark matter substructure through dynamical heating. We present a catalog…

astro-ph.GA2026

The impact of disc disruption on Milky Way satellite counts

Mark R. Lovell, Alexander H. Riley, Isabel Santos-Santos

Estimates for the total number of Milky Way (MW) satellites are often generated from a combination of the observed number of satellites in surveys, adjustments for the completeness…

astro-ph.GA2026

The Kinematically Hot, Extremely Metal-Poor C-19 Stellar Stream in DESI DR2

Nasser Mohammed, Joseph Y. Tang, Ting S. Li +47

Stellar streams are the result of a host galaxy's gravitational potential tidally disrupting satellite dwarf galaxies and globular clusters (GCs), causing them to grow leading and…

astro-ph.GA2025★ 1 cited

Forecasting Dark Matter Subhalo Constraints from Stellar Streams using Implicit Likelihood Inference

Tri Nguyen, Rutong Pei, Zhuofu Li +9

The evidence for dark matter (DM) remains compelling, although attempts to understand its particle nature remain inconclusive. One promising method to study DM is detecting DM subh…

astro-ph.GA2025★ 2 cited

Auriga Streams III: the mass-metallicity relation does not rule out tidal mass loss in Local Group satellites

Alexander H. Riley, Rebekka Bieri, Alis J. Deason +6

The mass-metallicity relation is a fundamental galaxy scaling law that has been extended to the faintest systems in the Local Group. We show that the small scatter in this relation…

astro-ph.GA2025★ 1 cited

The mass of the Milky Way from outer halo stars measured by DESI DR1

Gustavo E. Medina, Ting S. Li, Gwendolyn M. Eadie +50

As a benchmark for galaxy evolution and dark matter studies, the total mass of the Milky Way is a parameter of cosmological significance, and its value at large radii from the Gala…

astro-ph.GA2025

Not-so-heavy metal(s): Chemical Abundances in the Ultra-faint Dwarf Galaxies Eridanus IV and Centaurus I

Mairéad E Heiger, Alexander P Ji, Ting S Li +18

We present detailed chemical abundances of the brightest star in each of the ultra-faint dwarf galaxies Eridanus IV and Centaurus I using high-resolution Magellan/MIKE spectroscopy…

astro-ph.GA2025

The dark matter content of Milky Way dwarf spheroidal galaxies: Draco, Sextans and Ursa Minor

Hao Yang, Wenting Wang, Ling Zhu +50

The Milky Way Survey of the Dark Energy Spectroscopic Instrument (DESI) has so far observed three classical dwarf spheroidal galaxies (dSphs): Draco, Sextans and Ursa Minor. Based…

astro-ph.GA2025

The DECam MAGIC Survey: Spectroscopic Follow-up of the Most Metal-Poor Stars in the Distant Milky Way Halo

Vinicius M. Placco, Guilherme Limberg, Anirudh Chiti +21

In this work, we present high-resolution spectroscopic observations for six metal-poor stars with [Fe/H]<-3 (including one with [Fe/H]<-4), selected using narrow-band Ca II HK phot…

astro-ph.GA2025★ 5 cited

Nearby stellar substructures in the Galactic halo from DESI Milky Way Survey Year 1 Data Release

Bokyoung Kim, Sergey E. Koposov, Ting S. Li +41

We report five nearby ( kpc) stellar substructures in the Galactic halo from a subset of 138,661 stars in the Dark Energy Spectroscopic Instrument (DESI) Mi…

astro-ph.GA2025★ 1 cited

The Cocytos Stream: A Disrupted Globular Cluster from our Last Major Merger?

Christian Aganze, Vedant Chandra, Risa H. Wechsler +48

The census of stellar streams and dwarf galaxies in the Milky Way provides direct constraints on galaxy formation models and the nature of dark matter. The DESI Milky Way survey --…

astro-ph.GA2025

Streams, Shells, and Substructures in the Accretion-Built Stellar Halo of NGC 300

Catherine E. Fielder, David J. Sand, Michael G. Jones +27

We present deep optical observations of the stellar halo of NGC 300, an LMC-mass galaxy, acquired with the DEEP sub-component of the DECam Local Volume Exploration survey (DELVE) u…

astro-ph.GA2024★ 3 cited

Auriga Streams II: orbital properties of tidally disrupting satellites of Milky Way-mass galaxies

Nora Shipp, Alexander H. Riley, Christine M. Simpson +7

Galaxies like the Milky Way are surrounded by complex populations of satellites at all stages of tidal disruption. In this paper, we present a dynamical study of the disrupting sat…

astro-ph.GA2024★ 18 cited

Exploring the interaction between the MW and LMC with a large sample of blue horizontal branch stars from the DESI survey

Amanda Byström, Sergey E. Koposov, Sophia Lilleengen +42

The Large Magellanic Cloud (LMC) is a Milky Way (MW) satellite that is massive enough to gravitationally attract the MW disc and inner halo, causing significant motion of the inner…

astro-ph.GA2024★ 10 cited

Auriga Streams I: disrupting satellites surrounding Milky Way-mass haloes at multiple resolutions

Alexander H. Riley, Nora Shipp, Christine M. Simpson +8

In a hierarchically formed Universe, galaxies accrete smaller systems that tidally disrupt as they evolve in the host's potential. We present a complete catalogue of disrupting gal…