Gaia FGK Benchmark stars: Opening the black box of stellar element abundance determination

Gaia and its complementary spectroscopic surveys combined will yield the most comprehensive database of kinematic and chemical information of stars in the Milky Way. The Gaia FGK benchmark stars play a central role in this matter as they are calibration pillars for the atmospheric parameters and che...

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Detalles Bibliográficos
Autores: Jofré, P., Heiter, U., Worley, C. C., Blanco Cuaresma, S., Soubiran, C., Masseron, T., Hawkins, K., Adibekyan, V., Buder, S., Casamiquela, Laia, Gilmore, G., Hourihane, A., Tabernero, Hugo M.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2016
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/160590
Acceso en línea:https://hdl.handle.net/2445/160590
Access Level:acceso abierto
Palabra clave:Hipòtesi de Gaia
Estels
Via Làctia
Gaia hypothesis
Stars
Milky Way
Descripción
Sumario:Gaia and its complementary spectroscopic surveys combined will yield the most comprehensive database of kinematic and chemical information of stars in the Milky Way. The Gaia FGK benchmark stars play a central role in this matter as they are calibration pillars for the atmospheric parameters and chemical abundances for various surveys. The spectroscopic analyses of the benchmark stars are done by combining different methods, and the results will be affected by the systematic uncertainties inherent in each method. In this paper, we explore some of these systematic uncertainties. We determined line abundances of Ca, Cr, Mn and Co for four benchmark stars using six different methods. We changed the default input parameters of the different codes in a systematic way and found, in some cases, significant differences between the results. Since there is no consensus on the correct values for many of these default parameters, we urge the community to raise discussions towards standard input parameters that could alleviate the difference in abundances obtained by different methods. In this work, we provide quantitative estimates of uncertainties in elemental abundances due to the effect of differing technical assumptions in spectrum modelling.