J-PLUS: Beyond Spectroscopy III. Stellar Parameters and Elemental-abundance Ratios for Five Million Stars from DR3

Yang Huang; Timothy C. Beers; Kai Xiao; Haibo Yuan; Young Sun Lee; Hongrui Gu; Jihye Hong; Jifeng Liu; Zhou Fan; Paula Coelho; Patricia Cruz; F. J. Galindo-Guil; Simone Daflon; Fran Jiménez-Esteban; Javier Cenarro; David Cristóbal-Hornillos; Carlos Hernández-Monteagudo; Carlos López-Sanjuan; Antonio Marín-Franch; Mariano Moles; Jesús Varela; Héctor Vázquez Ramírez; Jailson Alcaniz; Renato Dupke; Alessandro Ederoclite; Laerte Sodré Jr.; Raul E. Angulo

arXiv · 2408.02171

J-PLUS: Beyond Spectroscopy III. Stellar Parameters and Elemental-abundance Ratios for Five Million Stars from DR3

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Abstract

We present a catalog of stellar parameters (effective temperature $T_{\rm eff}$, surface gravity $\log g$, age, and metallicity [Fe/H]) and elemental-abundance ratios ([C/Fe], [Mg/Fe], and [$α$/Fe]) for some five million stars (4.5 million dwarfs and 0.5 million giants stars) in the Milky Way, based on stellar colors from the Javalambre Photometric Local Universe Survey (J-PLUS) DR3 and \textit{Gaia} EDR3. These estimates are obtained through the construction of a large spectroscopic training set with parameters and abundances adjusted to uniform scales, and trained with a Kernel Principal Component Analysis. Owing to the seven narrow/medium-band filters employed by J-PLUS, we obtain precisions in the abundance estimates that are as good or better than derived from medium-resolution spectroscopy for stars covering a wide range of the parameter space: 0.10-0.20 dex for [Fe/H] and [C/Fe], and 0.05 dex for [Mg/Fe] and [$α$/Fe]. Moreover, systematic errors due to the influence of molecular carbon bands on previous photometric-metallicity estimates (which only included two narrow/medium-band blue filters) have now been removed, resulting in photometric-metallicity estimates down to [Fe/H] $\sim -4.0$, with typical uncertainties of 0.25 dex and 0.40 dex for dwarfs and giants, respectively. This large photometric sample should prove useful for the exploration of the assembly and chemical-evolution history of our Galaxy.

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Yang Huang, Timothy C. Beers, Kai Xiao, Haibo Yuan, Young Sun Lee, Hongrui Gu, Jihye Hong, Jifeng Liu, Zhou Fan, Paula Coelho, Patricia Cruz, F. J. Galindo-Guil, Simone Daflon, Fran Jiménez-Esteban, Javier Cenarro, David Cristóbal-Hornillos, Carlos Hernández-Monteagudo, Carlos López-Sanjuan, Antonio Marín-Franch, Mariano Moles, Jesús Varela, Héctor Vázquez Ramírez, Jailson Alcaniz, Renato Dupke, Alessandro Ederoclite, Laerte Sodré Jr., Raul E. Angulo. 2024-08-05. J-PLUS: Beyond Spectroscopy III. Stellar Parameters and Elemental-abundance Ratios for Five Million Stars from DR3. https://arxiv.org/abs/2408.02171

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