activity
20152026
most citedR-process enrichment from a single event in an ancient dwarf galaxy

402 citations · 1.9k across the 58 of their papers we have counts for

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48 papers · 1 filter

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

Chemo-dynamical Analysis of a CNO-Enhanced Ultra Metal-poor Star (): Insights into Early Enrichment by Faint Population III Supernova

Guilherme Limberg, Vinicius M. Placco, Alexander P. Ji +10

We report an independent identification of the ultra metal-poor (UMP) star () DR3 $\texttt{source_id}$ 4795913112968206720 (GDR3_479591) in the miss…

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

The DECam MAGIC Survey Mapping the Ancient Galaxy in CaHK: Overview and Summary of Early Science

A. Chiti, A. Drlica-Wagner, A. B. Pace +42

We present the DECam Mapping the Ancient Galaxy in CaHK (MAGIC) survey, a 54-night NOIRLab Survey Program to image 5,000deg of the southern hemisphere using a meta…

astro-ph.GA2026

The Metallicity Distribution of the Ultra-Faint Dwarf Galaxy Segue 1

Daisy Bissonette, Alexander P. Ji, Joshua D. Simon +6

Ultra-faint dwarf galaxies (UFDs; stellar masses ) offer unique insights into early chemical evolution in low-mass systems. However, interpreting their metalli…

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

A Chemodynamical Census of the Milky Way's Ultra-Faint Compact Satellites. I. A First Population-Level Look at the Internal Kinematics and Metallicities of 19 Extremely-Low-Mass Halo Stellar Systems

William Cerny, Ting S. Li, Andrew B. Pace +13

Deep, wide-area photometric surveys have uncovered a population of compact ( 1-15 pc), extremely-low-mass ( 20-4000 ) stellar systems in th…

astro-ph.GA2026

The DECam MAGIC Survey: Uncovering the Tidal Tails of the Crater II Dwarf Galaxy

Kaia R. Atzberger, Andrew B. Pace, Nitya Kallivayalil +27

Crater II (CraII), a large and low-density dwarf spheroidal galaxy, has unusual observed properties that are difficult to reproduce in cold dark matter simulations. Ongoing tidal d…

astro-ph.GA2025

No Observational Evidence for Dark Matter Nor a Large Metallicity Spread in the Extreme Milky Way Satellite Ursa Major III / UNIONS 1

William Cerny, Daisy Bissonette, Alexander P. Ji +9

The extremely-low-luminosity, compact Milky Way satellite Ursa Major III / UNIONS 1 (UMaIII/U1; ; pc) was found to have a substantial velocity d…

astro-ph.GA2025★ 3 cited

Ultra-Faint Milky Way Satellites Discovered in Carina, Phoenix, and Telescopium with DELVE Data Release 3

C. Y. Tan, W. Cerny, A. B. Pace +76

We report the discovery of three Milky Way satellite candidates: Carina IV, Phoenix III, and DELVE 7, in the third data release of the DECam Local Volume Exploration survey (DELVE)…

astro-ph.GA2025★ 2 cited

DELVE Milky Way Satellite Galaxy Census I: Satellite Population and Survey Selection Function in DES, DELVE, and Pan-STARRS

C. Y. Tan, A. Drlica-Wagner, A. B. Pace +84

The properties of Milky Way satellite galaxies have important implications for galaxy formation, reionization, and the fundamental physics of dark matter. However, the population o…

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★ 4 cited

A second-generation star in a relic dwarf galaxy

Anirudh Chiti, Vinicius M. Placco, Andrew B. Pace +22

Stars that contain only trace amounts of elements heavier than helium, referred to as having low "metallicity", preserve the chemical fingerprints of the first generation of stars…

astro-ph.GA2025★ 13 cited

Discovery of an Star in XP Spectra

Guilherme Limberg, Vinicius M. Placco, Alexander P. Ji +5

We report on the discovery of GDR3_526285 ( DR3 Source ID 5262850721755411072), a star with and one of the lowest metal ($\text{atomic number} >…

astro-ph.GA2025★ 1 cited

DELVE-ing into the Milky Way's Globular Clusters: Assessing extra-tidal features in NGC 5897, NGC 7492, and testing detectability with deeper photometry

A. Chiti, K. Tavangar, P. S. Ferguson +22

Extra-tidal features around globular clusters (GCs) are tracers of their disruption, stellar stream formation, and their host's gravitational potential. However, these features rem…

astro-ph.GA2025★ 1 cited

What Sets the Metallicity of Ultra-Faint Dwarfs?

Vance Wheeler, Andrey Kravtsov, Anirudh Chiti +2

We use intergalactic medium (IGM) metallicity distributions from several state-of-the-art cosmological simulations of Milky Way analogs and a semi-analytic model of ultra-faint dwa…

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★ 9 cited

Spectroscopic Analysis of Pictor II: a very low metallicity ultra-faint dwarf galaxy bound to the Large Magellanic Cloud

A. B. Pace, T. S. Li, A. P. Ji +30

We present Magellan/IMACS and Magellan/MIKE spectroscopy of the ultra-faint dwarf (UFD) galaxy Pictor~II (Pic~II) that is located only 12 kpc from the Large Magellanic Cloud (LMC).…

astro-ph.GA2025★ 3 cited

A Bimodal Metallicity Distribution Function in the Ultra-Faint Dwarf Galaxy Reticulum II

Alice M. Luna, Alexander P. Ji, Anirudh Chiti +6

Star formation in ultra-faint dwarf galaxies (UFDs, ) is suppressed by reionization, but may not be completely quenched. The metallicity distribution function (MD…

astro-ph.GA2025

The DECam MAGIC Survey: A Wide-field Photometric Metallicity Study of the Sculptor Dwarf Spheroidal Galaxy

Fabrícia O. Barbosa, Anirudh Chiti, Guilherme Limberg +26

The metallicity distribution function and internal chemical variations of a galaxy are fundamental to understand its formation and assembly history. In this work, we analyze photom…

astro-ph.GA2025

Early r-process Enrichment and Hierarchical Assembly Across the Sagittarius Dwarf Galaxy

Xiaowei Ou, Alexander Yelland, Anirudh Chiti +3

Dwarf galaxies like Sagittarius (Sgr) provide a unique window into the early stages of galactic chemical evolution, particularly through their metal-poor stars. By studying the che…

astro-ph.GA2024

Discovery and Spectroscopic Confirmation of Aquarius III: A Low-Mass Milky Way Satellite Galaxy

W. Cerny, A. Chiti, M. Geha +37

We present the discovery of Aquarius III, an ultra-faint Milky Way satellite galaxy identified in the second data release of the DECam Local Volume Exploration (DELVE) survey. Base…

astro-ph.GA2024★ 19 cited

A Pride of Satellites in the Constellation Leo? Discovery of the Leo VI Milky Way Satellite Galaxy with DELVE Early Data Release 3

C. Y. Tan, W. Cerny, A. Drlica-Wagner +32

We report the discovery and spectroscopic confirmation of an ultra-faint Milky Way (MW) satellite in the constellation of Leo. This system was discovered as a spatial overdensity o…

astro-ph.GA2024

Stellar Metallicities from DECam -band Photometry: A Study of Milky Way Ultra-Faint Dwarf Galaxies

Yue Pan, Anirudh Chiti, Alex Drlica-Wagner +5

We conducted an in-depth analysis of candidate member stars located in the peripheries of three ultra-faint dwarf (UFD) galaxy satellites of the Milky Way: Boötes I (Boo1), Boötes…