Year: 2017
Type: article
Abstract: We measure carbon and nitrogen abundances to a precision of dex for 450,000 giant stars from their low-resolution ( ) LAMOST DR2 survey spectra. We use these and measurements, together with empirical relations based on the APOKASC sample, to infer stellar masses and implied ages for 230,000 of these objects to 0.08 dex and 0.2 dex respectively. We use The Cannon , a data-driven approach to spectral modeling, to construct a predictive model for LAMOST spectra. Our reference set comprises 8125 stars observed in common between the APOGEE and LAMOST surveys, taking seven APOGEE DR12 labels (parameters) as ground truth: , , , , , , and . We add seven colors to the Cannon model, based on the g, r, i, J, H, K, W1, W2 magnitudes from APASS, 2MASS, and WISE , which improves our constraints on and by up to 20% and on by up to 70%. Cross-validation of the model demonstrates that, for high- objects, our inferred labels agree with the APOGEE values to within 50 K in temperature, 0.04 mag in , and dex in , , , , and . We apply the model to 450,000 giants in LAMOST DR2 that have not been observed by APOGEE. This demonstrates that precise individual abundances can be measured from low-resolution spectra and represents the largest catalog to date of homogeneous stellar , , masses, and ages. As a result
Source: The Astrophysical Journal
Authors: Anna Y. Q. Ho, Hans-Walter Rix, Melissa K. Ness, David W. Hogg, Chao Liu, Yuan-Sen 源森 Ting 丁
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Funders: National Science Foundation, Smithsonian Institution, U.S. Department of Energy, National Aeronautics and Space Administration, Alfred P. Sloan Foundation, Yale University, Carnegie Institution of Washington, Vanderbilt University, Ohio State University, California Institute of Technology, Adolph C. and Mary Sprague Miller Institute for Basic Research in Science, University of California Berkeley, University of Utah, University of Washington, Johns Hopkins University, Carnegie Mellon University, University of Notre Dame, University of Portsmouth, New Mexico State University, York University, University of Oxford, European Commission, University of New South Wales, National Natural Science Foundation of China, Chinese Academy of Sciences, Ministério da Ciência, Tecnologia e Inovação, Universidad Nacional Autónoma de México, National Development and Reform Commission, Max-Planck-Institut für Astrophysik, Max-Planck-Institut für Astronomie, Instituto de Astrofísica de Canarias, Office of Science, University of Colorado Boulder, Smithsonian Astrophysical Observatory, Leibniz-Gemeinschaft, National Astronomical Observatories, Chinese Academy of Sciences, Lawrence Berkeley National Laboratory
Awards: G158117727, G2354411687, G2845385625, GAMMA-RAY BURSTS (GRBS) AND THEIR AFTERGLOWS ARE PRIMARY TARGETS OF NASA'S SWIFT AND GLAST SPACE MIS, G4580503336, 使用LAMOST大样本巨星研究银河系的质量分布, G5933993633, Graduate Research Fellowship Program (GRFP), CDI-Type I: A Unified Probabilistic Model of Astronomical Imaging, G7336563035, G8689889895, G964417733, G988696487
OpenAlex ID: W2520362738