Rossiter-McLaughlin observations of 55 Cnc e

Research output: Contribution to journalArticlepeer-review


  • M. López-Morales
  • F. Rodler
  • Xavier Dumusque
  • L. A. Buchhave
  • A. Harutyunyan
  • S. Hoyer
  • R. Alonso
  • M. Gillon
  • N. A. Kaib
  • D. W. Latham
  • Christophe Lovis
  • F. Pepe
  • Didier Queloz
  • S. N. Raymond
  • D. Ségransan
  • I. P. Waldmann
  • S. Udry

Colleges, School and Institutes


We present Rossiter-McLaughlin observations of the transiting super-Earth 55 Cnc e collected during six transit events between 2012 January and 2013 November with HARPS and HARPS-N. We detect no radial velocity signal above 35 cm s-1 (3σ) and confine the stellar v sin ito 0.2 ± 0.5 km s-1. The star appears to be a very slow rotator, producing a very low amplitude Rossiter-McLaughlin effect. Given such a low amplitude, the Rossiter-McLaughlin effect of 55 Cnc e is undetected in our data, and any spin-orbit angle of the system remains possible. We also performed Doppler tomography and reach a similar conclusion. Our results offer a glimpse of the capacity of future instrumentation to study low amplitude Rossiter-McLaughlin effects produced by super-Earths.


Original languageEnglish
Article numberL31
Number of pages6
JournalAstrophysical Journal Letters
Issue number2
Early online date25 Aug 2014
Publication statusPublished - 10 Sep 2014


  • planets and satellites: formation, planets and satellites: individual (55 Cancri e), stars: individual (55 Cancri), techniques: radial velocities, techniques: spectroscopic