Publications (8)
The DESI Experiment, a whitepaper for Snowmass 2013
Michael Levi, Chris Bebek, Timothy Beers +11
The Dark Energy Spectroscopic Instrument (DESI) is a massively multiplexed fiber-fed spectrograph that will make the next major advance in dark energy in the timeframe 2018-2022. O…
The Earliest Phases of Galaxy Evolution
Cristina Chiappini, Francesca Matteucci, Timothy Beers +1
In this paper we study the very early phases of the evolution of our Galaxy by means of a chemical evolution model which reproduces most of the observational constraints in the sol…
Time-Resolved Spectroscopy with SDSS
Steven Bickerton, Carles Badenes, Thomas Hettinger +2
We present a brief technical outline of the newly-formed 'Detection of Spectroscopic Differences over Time' (DS/DT) project. Our collaboration is using the individual exposures fro…
Hubble Space Telescope Near-Ultraviolet Spectroscopy of the Bright CEMP-no Star BD+44 493
Vinicius Placco, Timothy Beers, Ian Roederer +10
We present an elemental-abundance analysis, in the near-ultraviolet (NUV) spectral range, for the extremely metal-poor star BD+44 493, a 9th magnitude sub-giant with [Fe/H] = -3.8…
Carbon-Enhanced Metal-Poor Stars: CEMP-s and CEMP-no Sub-Classes in the Halo System of the Milky Way
Daniela Carollo, Ken Freeman, Timothy Beers +3
We explore the kinematics and orbital properties of a sample of 323 very metal-poor stars in the halo system of the Milky Way, selected from the high-resolution spectroscopic follo…
The Frequency of Carbon-Enhanced Metal-Poor Stars in the Galaxy from the HERES sample
Sara Lucatello, Timothy Beers, Norbert Christlieb +5
We estimate the frequency of Carbon-Enhanced Metal-Poor (CEMP) stars among very metal-poor stars, based on an analysis of 349 stars with available high-resolution spectra observed…
Sodium and Oxygen Abundances in the Open Cluster NGC 6791 from APOGEE H-Band Spectroscopy
Katia Cunha, Verne V. Smith, Jennifer A. Johnson +27
The open cluster NGC 6791 is among the oldest, most massive and metal-rich open clusters in the Galaxy. High-resolution -band spectra from the Apache Point Observatory Galactic…
CN Anomalies in the Halo System and the Origin of Globular Clusters in the Milky Way
Daniela Carollo, Sarah Martell, Timothy Beers +1
We explore the kinematics and orbital properties of a sample of red giants in the halo system of the Milky Way that are thought to have formed in globular clusters, based on their…