Searching for new solar twins: The Inti survey for the Northern Sky

JHON YANA GALARZA; RICARDO LÓPEZ-VALDIVIA; DIEGO LORENZO-OLIVEIRA; HENRIQUE REGGIANI; JORGE MELÉNDEZ; DANIEL GAMARRA-SÁNCHEZ; FLORES MATÍAS ; JERRY PORTAL-RIVERA; PAULA MIQUELARENA; GEISA PONTE; KEVIN C. SCHLAUFMAN; TEÓFILO VARGAS AUCCALLA

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2021

0035-8711

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 Inti survey of new solar twins in the Northern Hemisphere. The spectra of our targets were initially obtained withspectrographs 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 ∼ 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 (𝜎(𝑇 eff ) = 15 K, 𝜎(log 𝑔) = 0.03 dex, 𝜎([Fe/H]) = 0.01 dex, and 𝜎(𝑣 𝑡 ) = 0.03 km 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 onmetallicity (−0.15 dex ≤ [Fe/H] ≤ +0.15 dex) and mass (0.95 M ≤ M ≤ 1.05 M ) 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 analogs and 13 solar-type stars. In addition, we identified 9 close solar twins whose stellar parameters are themost similar to those of the Sun.