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TOI 122b and TOI 237b, two small warm planets orbiting inactive M dwarfs, found by textit{TESS}

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 نشر من قبل William Waalkes
 تاريخ النشر 2020
  مجال البحث فيزياء
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We report the discovery and validation of TOI 122b and TOI 237b, two warm planets transiting inactive M dwarfs observed by textit{TESS}. Our analysis shows TOI 122b has a radius of 2.72$pm$0.18 R$_rm{e}$ and receives 8.8$pm$1.0$times$ Earths bolometric insolation, and TOI 237b has a radius of 1.44$pm$0.12 R$_rm{e}$ and receives 3.7$pm$0.5$times$ Earth insolation, straddling the 6.7$times$ Earth insolation that Mercury receives from the sun. This makes these two of the cooler planets yet discovered by textit{TESS}, even on their 5.08-day and 5.43-day orbits. Together, they span the small-planet radius valley, providing useful laboratories for exploring volatile evolution around M dwarfs. Their relatively nearby distances (62.23$pm$0.21 pc and 38.11$pm$0.23 pc, respectively) make them potentially feasible targets for future radial velocity follow-up and atmospheric characterization, although such observations may require substantial investments of time on large telescopes.



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