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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

The effect of stellar activity on the spectroscopic stellar parameters of the young solar twin HIP 36515

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Autor(es):
Galarza, Jhon Yana [1] ; Melendez, Jorge [1] ; Lorenzo-Oliveira, Diego [1] ; Valio, Adriana [2] ; Reggiani, Henrique [1] ; Carlos, Marilia [1] ; Ponte, Geisa [3, 2] ; Spina, Lorenzo [4] ; Haywood, Raphaelle D. [5] ; Gandolfi, Davide [6]
Número total de Autores: 10
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Dept Astron IAG USP, Rua Matao 1226, Cidade Univ, BR-05508900 Sao Paulo, SP - Brazil
[2] Univ Prebiteriana Mackenzie, CRAAM, Rua Consolacao 896, BR-01301000 Sao Paulo - Brazil
[3] Univ Fed Rio de Janeiro, Observ Valongo, Ladeira Pedro Antonio 43, BR-20080090 Rio De Janeiro, RJ - Brazil
[4] Monash Univ, Monash Ctr Astrophys, Sch Phys & Astron, Clayton, Vic 3800 - Australia
[5] Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 - USA
[6] Univ Torino, Dipartimento Fis, Via Pietro Giuria 1, I-10125 Turin - Italy
Número total de Afiliações: 6
Tipo de documento: Artigo Científico
Fonte: Monthly Notices of the Royal Astronomical Society; v. 490, n. 1, p. L86-L90, NOV 2019.
Citações Web of Science: 0
Resumo

Spectroscopic equilibrium allows us to obtain precise stellar parameters in Sun-like stars. It relies on the assumption of the iron excitation and ionization equilibrium. However, several works suggest that magnetic activity may affect chemical abundances of young active stars, calling into question the validity of this widely used method. We have tested, for the first time, variations in stellar parameters and chemical abundances for the young solar twin HIP 36515 (similar to 0.4 Gyr), along its activity cycle. This star has stellar parameters very well established in the literature and we estimated its activity cycle in similar to 6 yr. Using HARPS spectra with high resolving power (115 000) and signal-to-noise ratio (similar to 270), the stellar parameters of six different epochs in the cycle were estimated. We found that the stellar activity is strongly correlated with the effective temperature, metallicity, and microturbulence velocity. The possibility of changes in the Li I 6707.8 angstrom line due to flares and star-spots was also investigated. Although the core of the line profile shows some variations with the stellar cycle, it is compensated by changes in the effective temperature, resulting in a non-variation of the Li abundance. (AU)

Processo FAPESP: 16/20667-8 - Cronômetros estelares: a conexão entre idade, atividade cromosférica, rotação e abundâncias de lítio em estrelas de tipo solar
Beneficiário:Diego Lorenzo de Oliveira
Linha de fomento: Bolsas no Brasil - Pós-Doutorado
Processo FAPESP: 18/04055-8 - Espectroscopia de alta precisão: das primeiras estrelas aos planetas
Beneficiário:Jorge Luis Melendez Moreno
Linha de fomento: Auxílio à Pesquisa - Temático