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Two Planets Straddling the Habitable Zone of The Nearby K Dwarf Gl 414A

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 نشر من قبل Cayla Dedrick
 تاريخ النشر 2020
  مجال البحث فيزياء
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We present the discovery of two planets orbiting the nearby (D=11.9 pc) K7 dwarf Gl 414A. Gl 414A b is a sub-Neptune mass planet with M$_b sin{i_b} = 9.28^{+3.19}_{-2.54}$ M$_oplus$ and a semi-major axis of 0.24 $pm$ 0.01 au. Gl 414A c is a sub-Saturn mass planet with $M_c sin{i_c} = 59.48^{+9.98}_{-9.69}$ M$_oplus$ and a semi-major axis of 1.43 $pm$ 0.06 au. We jointly analyzed radial velocity data from Keck/HIRES and the Automated Planet Finder at Lick Observatory, as well as photometric data from KELT, to detect the two planets as well as two additional signals related to the rotationally-modulated activity and the long term magnetic activity cycle of the star. The outer planet in this system may be a potential candidate for future direct imaging missions.



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