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TOI-132 b: A short-period planet in the Neptune desert transiting a $V=11.3$ G-type star

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 نشر من قبل Mat\\'ias R. D\\'iaz
 تاريخ النشر 2019
  مجال البحث فيزياء
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The Neptune desert is a feature seen in the radius-mass-period plane, whereby a notable dearth of short period, Neptune-like planets is found. Here we report the {it TESS} discovery of a new short-period planet in the Neptune desert, orbiting the G-type dwarf TYC,8003-1117-1 (TOI-132). {it TESS} photometry shows transit-like dips at the level of $sim$1400 ppm occurring every $sim$2.11 days. High-precision radial velocity follow-up with HARPS confirmed the planetary nature of the transit signal and provided a semi-amplitude radial velocity variation of $sim$11.5 m s$^{-1}$, which, when combined with the stellar mass of $0.97pm0.06$ $M_{odot}$, provides a planetary mass of 22.83$^{+1.81}_{-1.80}$ $M_{oplus}$. Modeling the {it TESS} high-quality light curve returns a planet radius of 3.43$^{+0.13}_{-0.14}$ $R_{oplus}$, and therefore the planet bulk density is found to be 3.11$^{+0.44}_{-0.450}$ g cm$^{-3}$. Planet structure models suggest that the bulk of the planet mass is in the form of a rocky core, with an atmospheric mass fraction of 4.3$^{+1.2}_{-2.3}$%. TOI-132 b is a {it TESS} Level 1 Science Requirement candidate, and therefore priority follow-up will allow the search for additional planets in the system, whilst helping to constrain low-mass planet formation and evolution models, particularly valuable for better understanding the Neptune desert.


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