NGTS-4b: A sub-Neptune transiting in the desert

  title={NGTS-4b: A sub-Neptune transiting in the desert},
  author={Richard G. West and Edward Gillen and Daniel Bayliss and Matthew R. Burleigh and Laetitia Delrez and Maximilian N. G{\"u}nther and Simon T. Hodgkin and James A. G. Jackman and James S. Jenkins and George W King and J. McCormac and Louise D. Nielsen and Liam Raynard and Alexis M. S. Smith and M. G. Soto and Oliver Turner and Peter J. Wheatley and Yaseen Almleaky and David J Armstrong and Claudia Belardi and François Bouchy and Joshua T Briegal and Artem Burdanov and Juan Cabrera and Sarah L. Casewell and Alexander Chaushev and B. Chazelas and Paul Robin Brian Chote and Benjamin F Cooke and Sz. Csizmadia and Elsa Ducrot and Ph. Eigm{\"u}ller and Anders Erikson and Emma Foxell and Boris T. G{\"a}nsicke and Micha{\"e}l Gillon and M. R. Goad and Emmanuel Jehin and Gregory Lambert and Emma S. Longstaff and Tom Louden and M. Moyano and C. A. Murray and Don Pollacco and Didier Queloz and Heike Rauer and Sandrine Sohy and Samantha J. Thompson and St{\'e}phane Udry and Simon. R. Walker and Christopher A. Watson},
  journal={Monthly Notices of the Royal Astronomical Society},
  • R. West, E. Gillen, C. Watson
  • Published 3 September 2018
  • Geology, Physics
  • Monthly Notices of the Royal Astronomical Society
We report the discovery of NGTS-4b, a sub-Neptune-sized planet transiting a 13th magnitude K-dwarf in a 1.34 d orbit. NGTS-4b has a mass M=20.6 ± 3.0 M⊕ and radius R=3.18 ± 0.26 R⊕, which places it well within the so-called “Neptunian Desert”. The mean density of the planet (3.45 ± 0.95 g cm−3) is consistent with a composition of 100 % H2O or a rocky core with a volatile envelope. NGTS-4b is likely to suffer significant mass loss due to relatively strong EUV/X-ray irradiation. Its survival in… 

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