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arXiv · 2103.10112

The APOGEE Data Release 16 Spectral Line List

Verne V. Smith·Dmitry Bizyaev·Katia Cunha·Matthew D. Shetrone·Diogo Souto·Carlos Allende Prieto·Thomas Masseron·Szabolcs Meszaros·Henrik Jonsson·Sten Hasselquist·Yeisson Osorio·D. A. Garcia-Hernandez·Bertrand Plez·Rachael L. Beaton·Jon Holtzman·Steven R. Majewski·Guy S. Stringfellow·Jennifer Sobeck
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Abstract

The updated H-band spectral line list (from λ15,000 - 17,000Å) adopted by the Apache Point Observatory Galactic Evolution Experiment (APOGEE) for the SDSS IV Data Release 16 (DR16) is presented here. The APOGEE line list is a combination of atomic and molecular lines with data from laboratory, theoretical, and astrophysical sources. Oscillator strengths and damping constants are adjusted using high signal-to-noise, high-resolution spectra of the Sun and alpha Boo (Arcturus) as "standard stars". Updates to the DR16 line list, when compared to the previous DR14 version, are the inclusion of molecular H_2O and FeH lines, as well as a much larger (by a factor of ~4) atomic line list, which includes significantly more transitions with hyperfine splitting. More recent references and line lists for the crucial molecules CO and OH were used, as well as for C_2 and SiH. In contrast to DR14, DR16 contains measurable lines from the heavy neutron-capture elements cerium (as Ce II), neodymium (as Nd II), and ytterbium (as Yb II), as well as one line from rubidium (as Rb I), that may be detectable in a small fraction of APOGEE red giants.

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Verne V. Smith, Dmitry Bizyaev, Katia Cunha, Matthew D. Shetrone, Diogo Souto, Carlos Allende Prieto, Thomas Masseron, Szabolcs Meszaros, Henrik Jonsson, Sten Hasselquist, Yeisson Osorio, D. A. Garcia-Hernandez, Bertrand Plez, Rachael L. Beaton, Jon Holtzman, Steven R. Majewski, Guy S. Stringfellow, Jennifer Sobeck. 2021-03-18. The APOGEE Data Release 16 Spectral Line List. https://doi.org/10.3847/1538-3881%2Fabefdc

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