Oxford University Press (OUP), Monthly Notices of the Royal Astronomical Society, 2020
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Abstract The Neptune desert is a feature seen in the radius-period plane, whereby a notable dearth of short period, Neptune-like planets is found. Here we report the TESS discovery of a new short-period planet in the Neptune desert, orbiting the G-type dwarf TYC 8003-1117-1 (TOI-132). TESS photometry shows transit-like dips at the level of ∼1400 ppm occurring every ∼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 11.38 $^{+0.84}_{-0.85}$ m s−1, which, when combined with the stellar mass of 0.97 ± 0.06 M⊙, provides a planetary mass of 22.40$^{+1.90}_{-1.92}$ M⊕. Modeling the TESS light curve returns a planet radius of 3.42$^{+0.13}_{-0.14}$ R⊕, and therefore the planet bulk density is found to be 3.08$^{+0.44}_{-0.46}$ 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$^{+1.2}_{-2.3}$ per cent. TOI-132 b is a 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.