J-PLUS: Identification of low-metallicity stars with artificial neural networks using SPHINX

Autor: R. Lopes de Oliveira, C. López-Sanjuan, Young Sun Lee, David Cristóbal-Hornillos, Laerte Sodré, S. Daflon, Silvia Rossi, Vinicius M. Placco, Thomas Masseron, Antonio Marín-Franch, José Antonio Ruiz Caballero, Ana L. Chies-Santos, M. Borges Fernandes, H. Vázquez Ramió, Stavros Akras, Charles Jose Bonatto, Alessandro Ederoclite, Devin D. Whitten, A. J. Cenarro, C. Mendes de Oliveira, Mariano Moles, R. A. Dupke, Alvaro Orsi, Timothy C. Beers, M. V. Costa-Duarte, Paula Coelho, Jesús A. Varela
Rok vydání: 2019
Předmět:
Zdroj: Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual)
Universidade de São Paulo (USP)
instacron:USP
ISSN: 1432-0746
0004-6361
Popis: We present a new methodology for the estimation of stellar atmospheric parameters from narrow- and intermediate-band photometry of the Javalambre Photometric Local Universe Survey (J-PLUS), and propose a method for target pre-selection of low-metallicity stars for follow-up spectroscopic studies. Photometric metallicity estimates for stars in the globular cluster M15 are determined using this method. By development of a neural-network-based photometry pipeline, we aim to produce estimates of effective temperature, $T_{\rm eff}$, and metallicity, [Fe/H], for a large subset of stars in the J-PLUS footprint. The Stellar Photometric Index Network Explorer, SPHINX, is developed to produce estimates of $T_{\rm eff}$ and [Fe/H], after training on a combination of J-PLUS photometric inputs and synthetic magnitudes computed for medium-resolution (R ~ 2000) spectra of the Sloan Digital Sky Survey. This methodology is applied to J-PLUS photometry of the globular cluster M15. Effective temperature estimates made with J-PLUS Early Data Release photometry exhibit low scatter, \sigma($T_{\rm eff}$) = 91 K, over the temperature range 4500 < $T_{\rm eff}$ (K) < 8500. For stars from the J-PLUS First Data Release with 4500 < $T_{\rm eff}$ (K) < 6200, 85 $\pm$ 3% of stars known to have [Fe/H]
Comment: 18 pages, 12 figures
Databáze: OpenAIRE