Eugenia Diaz-Giménez | Observatório Astronómico de Córdoba - Argentina
Uma busca por aglomerados estelares jovens com métodos de aprendizado de máquina
O universo em 3-D: astrofísica com grandes levantamentos de galáxias
Texto completo | |
Autor(es): Mostrar menos - |
Galarza, Jhon Yana
[1]
;
Lopez-Valdivia, Ricardo
[2]
;
Lorenzo-Oliveira, Diego
[1]
;
Reggiani, Henrique
[3]
;
Melendez, Jorge
[1]
;
Gamarra-Sanchez, Daniel
[4]
;
Flores, Matias
[5, 6, 7]
;
Portal-Rivera, Jerry
[4]
;
Miquelarena, Paula
[5, 6, 7]
;
Ponte, Geisa
[1, 8]
;
Schlaufman, Kevin C.
[3]
;
Auccalla, Teofilo Vargas
[4]
Número total de Autores: 12
|
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 Texas Austin, Dept Astron, 2515 Speedway, Stop C1400, Austin, TX 78712 - USA
[3] Dept Phys & Astron, Johns Hopkins Univ, 3400 N Charles St, Baltimore, MD 21218 - USA
[4] Univ Nacl Mayor San Marcos, Fac Ciencias Fis, Seminario Permanente Astron & Ciencias Espaciales, Ave Venezuela S-N, Lima 15081 - Peru
[5] Univ Nacl San Juan, Fac Ciencias Exactas Fis & Nat, J5402DCS, San Juan - Argentina
[6] Consejo Nacl Invest Cient & Tecn CONICET, C1425FQB, Buenos Aires, DF - Argentina
[7] Inst Ciencias Astron Tierra & Espacio ICATE, Espana Sur 1512, CC 49, RA-5400 San Juan - Argentina
[8] Univ Prebiteriana Mackenzie, CRAAM, Rua Consolacao 896, Sao Paulo, SP - Brazil
Número total de Afiliações: 8
|
Tipo de documento: | Artigo Científico |
Fonte: | Monthly Notices of the Royal Astronomical Society; v. 504, n. 2, p. 1873-1887, JUN 2021. |
Citações Web of Science: | 0 |
Resumo | |
Solar twins are key in different areas of astrophysics, however only just over a hundred were identified and well-studied in the last two decades. In this work, we take advantage of the very precise Gaia (DR2/EDR3), Tycho, and 2MASS photometric systems to create the survey of new solar twins in the Northern Hemisphere. The spectra of our targets were initially obtained with spectrographs of moderate resolution (ARCES and Goodman spectrographs with R = 31500 and 11930, respectively) to find the best solar twin candidates and then observed at McDonald Observatory with higher resolving power (TS23, R = 60000) and signal-to-noise ratio (SNR similar to 300-500). The stellar parameters were estimated through the differential spectroscopic equilibrium relative to the Sun, which allow us to achieve a high internal precision (sigma(T-eff) = 15K, sigma(log g) = 0.03dex, sigma({[}Fe/H]) = 0.01dex, and sigma(v(t)) = 0.03km s(-1)). We propose a new class of stars with evolution similar to the Sun: solar proxy, which is useful to perform studies related to the evolution of the Sun, such as its rotational and magnetic evolution. Its definition is based on metallicity (-0.15dex <= {[}Fe/H] <= + 0.15dex) and mass (0.95M(circle dot) <= M <= 1.05M(circle dot)) constraints, thus assuring that the star follows a similar evolutionary path as the Sun along the main sequence. Based on this new definition, we report 70 newly identified solar proxies, 46 solar analogues, and 13 solar-type stars. In addition, we identified nine close solar twins whose stellar parameters are the most similar to those of the Sun. (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 |
Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
Processo FAPESP: | 18/04055-8 - Espectroscopia de alta precisão: das primeiras estrelas aos planetas |
Beneficiário: | Jorge Luis Melendez Moreno |
Modalidade de apoio: | Auxílio à Pesquisa - Temático |