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arXiv · 2202.10102

Chemical Composition Of Bright Stars In The Northern Hemisphere: Star-Planet Connection

Abstract

In fulfilling the aims of the planetary and asteroseismic research missions, such as that of the NASA Transiting Exoplanet Survey Satellite (TESS) space telescope, accurate stellar atmospheric parameters and a detailed chemical composition are required as input. We have observed high-resolution spectra for all 848 bright (V<8 mag) stars that are cooler than F5 spectral class in the area up to 12 deg surrounding the northern TESS continuous viewing zone and uniformly determined the main atmospheric parameters, ages, orbital parameters, velocity components, and precise abundances of up to 24 chemical species (C(C2), N(CN), [O I], Na I, Mg I, Al I, Si I, Si I, Ca I, Ca II, Sc I, Sc II, Ti I, Ti II, V I, Cr I, Cr II, Mn I, Fe I, Fe II, Co I, Ni I, Cu I, and Zn I) for 740 slowly rotating stars. The analysis of 25 planet-hosting stars in our sample drove us to the following conclusions: the dwarf stars hosting high-mass planets are more metal rich than those with low-mass planets. We find slightly negative C/O and Mg/Si slopes toward the stars with high-mass planets. All the low-mass planet hosts in our sample show positive $Δ$[El/Fe] versus condensation temperature slopes, in particular, the star with the large number of various planets. The high-mass planet hosts have a diversity of slopes, but in more metal rich, older, and cooler stars, the positive elemental abundance slopes are more common.

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G. Tautvaišienė, Š. Mikolaitis, A. Drazdauskas, E. Stonkutė, R. Minkevičiūtė, E. Pakštienė, H. Kjeldsen, K. Brogaard, Y. Chorniy, C. von Essen, F. Grundahl, M. Ambrosch, V. Bagdonas, A. Sharma, C. Viscasillas Vázquez. 2022-02-21. Chemical Composition Of Bright Stars In The Northern Hemisphere: Star-Planet Connection. https://doi.org/10.3847/1538-4365%2Fac50b5

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