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Judith Korth



The discovery and mass measurement of a new ultra-short-period Planet : K2-131b


  • Fei Dai
  • Joshua N. Winn
  • Davide Gandolfi
  • Sharon X. Wang
  • Johanna K. Teske
  • Jennifer Burt
  • Simon Albrecht
  • Oscar Barragán
  • William D. Cochran
  • Michael Endl
  • Malcolm Fridlund
  • Artie P. Hatzes
  • Teruyuki Hirano
  • Lea A. Hirsch
  • Marshall C. Johnson
  • Anders Bo Justesen
  • John Livingston
  • Carina M. Persson
  • Jorge Prieto-Arranz
  • Andrew Vanderburg
  • Roi Alonso
  • Giuliano Antoniciello
  • Pamela Arriagada
  • R. P. Butler
  • Juan Cabrera
  • Jeffrey D. Crane
  • Felice Cusano
  • Szilárd Csizmadia
  • Hans Deeg
  • Sergio B. Dieterich
  • Philipp Eigmüller
  • Anders Erikson
  • Mark E. Everett
  • Akihiko Fukui
  • Sascha Grziwa
  • Eike W. Guenther
  • Gregory W. Henry
  • Steve B. Howell
  • John Asher Johnson
  • Judith Korth
  • Masayuki Kuzuhara
  • Norio Narita
  • David Nespral
  • Grzegorz Nowak
  • Enric Palle
  • Martin Pätzold
  • Heike Rauer
  • Pilar Montañés Rodríguez
  • Stephen A. Shectman
  • Alexis M.S. Smith
  • Ian B. Thompson
  • Vincent Van Eylen
  • Michael W. Williamson
  • Robert A. Wittenmyer

Summary, in English

We report the discovery of a new ultra-short-period planet and summarize the properties of all such planets for which the mass and radius have been measured. The new planet, K2-131b, was discovered in K2 Campaign 10. It has a radius of and orbits a G dwarf with a period of 8.9 hr. Radial velocities obtained with Magellan/PFS and TNG/HARPS-N show evidence for stellar activity along with orbital motion. We determined the planetary mass using two different methods: (1) the "floating chunk offset" method, based only on changes in velocity observed on the same night; and (2) a Gaussian process regression based on both the radial velocity and photometric time series. The results are consistent and lead to a mass measurement of and a mean density of g cm-3.

Publishing year





Astronomical Journal





Document type

Journal article


IOP Publishing


  • individual (EPIC 228732031)
  • planetary systems - stars




  • ISSN: 0004-6256