342 citations · 6.5k across the 144 of their papers we have counts for
15 papers · 1 filter
The Metallicity Gradient and Complex Formation History of the Outermost Halo of the Milky Way
Sarah E. Dietz, Jinmi Yoon, Timothy C. Beers +1
We present an examination of the metallicity distribution function of the outermost stellar halo of the Galaxy based on an analysis of both local (within 4 kpc of the Sun, ~16,500…
Dynamical Relics of the Ancient Galactic Halo
Zhen Yuan, G. C. Myeong, Timothy C. Beers +11
We search for dynamical substructures in the LAMOST DR3 very metal-poor (VMP) star catalog. After cross-matching with Gaia DR2, there are 3300 VMP stars with available high-quality…
Chandra Observations of the Spectacular A3411-12 Merger Event
Felipe Andrade-Santos, Reinout J. van Weeren, Gabriella Di Gennaro +17
We present deep Chandra observations of A3411-12, a remarkable merging cluster that hosts the most compelling evidence for electron re-acceleration at cluster shocks to date. Using…
Identification of a Group III CEMP-no Star in the Dwarf Spheroidal Galaxy Canes Venatici I
Jinmi Yoon, Devin D. Whitten, Timothy C. Beers +3
CEMP-no stars, a subclass of carbon-enhanced metal-poor (CEMP) stars, are one of the most significant stellar populations in Galactic Archaeology, because they dominate the low end…
Constraints on the Galactic Inner Halo Assembly History from the Age Gradient of Blue Horizontal-branch Stars
Devin D. Whitten, Timothy C. Beers, Vinicius M. Placco +6
We present an analysis of the relative age distribution of the Milky Way halo, based on samples of blue horizontal-branch (BHB) stars obtained from the Panoramic Survey Telescope a…
J-PLUS: photometric calibration of large area multi-filter surveys with stellar and white dwarf loci
C. López-Sanjuan, J. Varela, D. Cristóbal-Hornillos +22
We present the photometric calibration of the twelve optical passbands observed by the Javalambre Photometric Local Universe Survey (J-PLUS). The proposed calibration method has fo…
Assessing the photometric redshift precision of the S-PLUS survey: the Stripe-82 as a test-case
A. Molino, M. V. Costa-Duarte, L. Sampedro +42
In this paper we present a thorough discussion about the photometric redshift (photo-z) performance of the Southern Photometric Local Universe Survey (S-PLUS). This survey combines…
Metal-poor Stars Observed with the Automated Planet Finder Telescope. II. Chemodynamical Analysis of Six Low-Metallicity Stars in the Halo System of the Milky Way
Mohammad K. Mardini, Vinicius M. Placco, Ali Taani +2
In this work, we study the chemical compositions and kinematic properties of six metal-poor stars with [Fe/H] in the Galactic halo. From high-resolution (R ~110,000)…
Metal-poor stars observed with the automated planet finder telescope. I. Discovery of five carbon-enhanced metal-poor stars from LAMOST
Mohammad K. Mardini, Haining Li, Vinicius M. Placco +6
We report on the discovery of five carbon-enhanced metal-poor (CEMP) stars in the metallicity range of [Fe/H] . These stars were selected from the LAMOST DR3 low-res…
The Detailed Science Case for the Maunakea Spectroscopic Explorer, 2019 edition
The MSE Science Team, Carine Babusiaux, Maria Bergemann +258
(Abridged) The Maunakea Spectroscopic Explorer (MSE) is an end-to-end science platform for the design, execution and scientific exploitation of spectroscopic surveys. It will unvei…
Evidence for an aspherical Population III supernova explosion inferred from the hyper metal-poor star HE1327-2326
Rana Ezzeddine, Anna Frebel, Ian U. Roederer +6
We present observational evidence that an aspherical supernova explosion could have occurred in the First stars in the early universe. Our results are based on the First determinat…
Discovery of a new stellar sub-population residing in the (inner) stellar halo of the Milky Way
José G. Fernández-Trincado, Timothy C. Beers, Vinicius M. Placco +8
We report the discovery of a unique collection of metal-poor giant-stars, that exhibit anomalously high levels of Si, clearly above typical Galactic levels. Our sample spans…
The R-Process Alliance: Discovery of a low-alpha, r-Process-Enhanced Metal-Poor Star in the Galactic Halo
Charli M. Sakari, Ian U. Roederer, Vinicius M. Placco +24
A new moderately r-process-enhanced metal-poor star, RAVE J093730.5-062655, has been identified in the Milky Way halo as part of an ongoing survey by the R-Process Alliance. The te…
Discovery of a nitrogen-enhanced mildly metal-poor binary system: Possible evidence for pollution from an extinct AGB Star
José G. Fernández-Trincado, Ronald Mennickent, Mauricio Cabezas +13
We report the serendipitous discovery of a nitrogen-rich, mildly metal-poor ([Fe/H]=-1.08) giant star in a single-lined spectroscopic binary system found in the SDSS-IV Apache Poin…
Abundances and kinematics of carbon-enhanced metal-poor stars in the Galactic halo*; A new classification scheme based on Sr and Ba
Camilla J. Hansen, Terese T. Hansen, Andreas Koch +4
Carbon-enhanced metal-poor (CEMP) stars span a wide range of stellar populations, from bona fide second-generation stars to later forming stars that provide excellent probes of, e.…