TY - JOUR
T1 - The GALAH+ Survey
T2 - Third Data Release
AU - Buder, Sven
AU - Sharma, Sanjib
AU - Kos, Janez
AU - Amarsi, Anish M.
AU - Nordlander, Thomas
AU - Lind, Karin
AU - Martell, Sarah L.
AU - Asplund, Martin
AU - Bland-Hawthorn, Joss
AU - Casey, Andrew R.
AU - Silva, Gayandhi M. De
AU - D'Orazi, Valentina
AU - Freeman, Ken C.
AU - Hayden, Michael R.
AU - Lewis, Geraint F.
AU - Lin, Jane
AU - Schlesinger, Katharine J.
AU - Simpson, Jeffrey D.
AU - Stello, Dennis
AU - Zucker, Daniel B.
AU - Zwitter, Tomaz
AU - Beeson, Kevin L.
AU - Buck, Tobias
AU - Casagrande, Luca
AU - Clark, Jake T.
AU - Cotar, Klemen
AU - Costa, Gary S. Da
AU - Grijs, Richard de
AU - Feuillet, Diane
AU - Horner, Jonathan
AU - Kafle, Prajwal R.
AU - Khanna, Shourya
AU - Kobayashi, Chiaki
AU - Liu, Fan
AU - Montet, Benjamin T.
AU - Nandakumar, Govind
AU - Nataf, David M.
AU - Ness, Melissa K.
AU - Spina, Lorenzo
AU - Tepper-Garcia, Thor
AU - Ting, Yuan-Sen
AU - Traven, Gregor
AU - Vogrincic, Rok
AU - Wittenmyer, Robert A.
AU - Wyse, Rosemary F. G.
AU - Zerjal, Marusa
AU - collaboration, the GALAH
N1 - © 2021 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1093/mnras/stab1242
PY - 2021/5/6
Y1 - 2021/5/6
N2 - The ensemble of chemical element abundance measurements for stars, along with precision distances and orbit properties, provides high-dimensional data to study the evolution of the Milky Way. With this third data release of the Galactic Archaeology with HERMES (GALAH) survey, we publish 678 423 spectra for 588 571 mostly nearby stars (81.2% of stars are within 75 stellar clusters. We derive stellar parameters $T_\text{eff}$, $\log g$, [Fe/H], $v_\text{mic}$, $v_\text{broad}$ & $v_\text{rad}$ using our modified version of the spectrum synthesis code Spectroscopy Made Easy (SME) and 1D MARCS model atmospheres. We break spectroscopic degeneracies in our spectrum analysis with astrometry from $Gaia$ DR2 and photometry from 2MASS. We report abundance ratios [X/Fe] for 30 different elements (11 of which are based on non-LTE computations) covering five nucleosynthetic pathways. We describe validations for accuracy and precision, flagging of peculiar stars/measurements and recommendations for using our results. Our catalogue comprises 65% dwarfs, 34% giants, and 1% other/unclassified stars. Based on unflagged chemical composition and age, we find 62% young low-$\alpha$, 9% young high-$\alpha$, 27% old high-$\alpha$, and 2% stars with $\mathrm{[Fe/H]} \leq -1$. Based on kinematics, 4% are halo stars. Several Value-Added-Catalogues, including stellar ages and dynamics, updated after $Gaia$ eDR3, accompany this release and allow chrono-chemodynamic analyses, as we showcase.
AB - The ensemble of chemical element abundance measurements for stars, along with precision distances and orbit properties, provides high-dimensional data to study the evolution of the Milky Way. With this third data release of the Galactic Archaeology with HERMES (GALAH) survey, we publish 678 423 spectra for 588 571 mostly nearby stars (81.2% of stars are within 75 stellar clusters. We derive stellar parameters $T_\text{eff}$, $\log g$, [Fe/H], $v_\text{mic}$, $v_\text{broad}$ & $v_\text{rad}$ using our modified version of the spectrum synthesis code Spectroscopy Made Easy (SME) and 1D MARCS model atmospheres. We break spectroscopic degeneracies in our spectrum analysis with astrometry from $Gaia$ DR2 and photometry from 2MASS. We report abundance ratios [X/Fe] for 30 different elements (11 of which are based on non-LTE computations) covering five nucleosynthetic pathways. We describe validations for accuracy and precision, flagging of peculiar stars/measurements and recommendations for using our results. Our catalogue comprises 65% dwarfs, 34% giants, and 1% other/unclassified stars. Based on unflagged chemical composition and age, we find 62% young low-$\alpha$, 9% young high-$\alpha$, 27% old high-$\alpha$, and 2% stars with $\mathrm{[Fe/H]} \leq -1$. Based on kinematics, 4% are halo stars. Several Value-Added-Catalogues, including stellar ages and dynamics, updated after $Gaia$ eDR3, accompany this release and allow chrono-chemodynamic analyses, as we showcase.
KW - astro-ph.GA
KW - astro-ph.SR
U2 - 10.1093/mnras/stab1242
DO - 10.1093/mnras/stab1242
M3 - Article
SN - 0035-8711
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
M1 - stab1242
ER -