342 citations · 6.5k across the 144 of their papers we have counts for
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The R-Process Alliance: Exploring the cosmic scatter among ten r-process sites with stellar abundances
Mila Racca, Terese T. Hansen, Ian U. Roederer +11
The astrophysical origin of the rapid neutron-capture process (r-process), which produces about half of the elements heavier than iron, remains uncertain. The oldest, most metal-po…
Abundances of Rarely Detected s-process Elements Derived from the Ultraviolet Spectrum of the s-process-enhanced Metal-poor Star HD 196944
Ian U. Roederer, Vinicius M. Placco, Amanda I. Karakas +2
We present an analysis of the heavy-element abundances of HD 196944, a carbon-enhanced metal-poor (CEMP) star enriched with elements produced by the slow neutron-capture process (s…
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…
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…
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} >…
Abundances of P, S, and K in 58 bulge spheroid stars from APOGEE
B. Barbuy, H. Ernandes, A. C. S. Friaça +25
We have previously studied several elements in 58 selected bulge spheroid stars, based on spectral lines in the H-band. We now derive the abundances of the less-studied elements ph…
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…
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).…
Probing Abundance Variations among Multiple Stellar Populations in the Metal-Poor Globular Cluster NGC 2298 using Gemini-South/GHOST
Avrajit Bandyopadhyay, Rana Ezzeddine, Vinicius M. Placco +3
Studying the abundances in metal-poor globular clusters is crucial for understanding the formation of the Galaxy and the nucleosynthesis processes in the early Universe. We observe…
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…
The R-Process Alliance: Hunting for gold in the near-UV spectrum of 2MASS J05383296-5904280
Terese T. Hansen, Ian U. Roederer, Shivani P. Shah +10
Context. Over the past few years, the -Process Alliance (RPA) has successfully carried out a search for stars that are highly enhanced in elements produced via the rapid neutron…
Elemental abundances of 44 very metal-poor stars determined from Subaru/IRD near-infrared spectra
Wako Aoki, Timothy C. Beers, Satoshi Honda +12
Abundances of five elements, Na, Mg, Al, Si, and Sr, are investigated for 44 very metal-poor stars (-4.0 < [Fe/H] < -1.5) in the Galactic halo system based on an Local Thermodinami…