Measurement of the nodal precession of WASP-33 b via doppler tomography

Marshall C. Johnson, William D. Cochran, Andrew Collier Cameron, Daniel Bayliss

Research output: Contribution to journalArticlepeer-review

25 Citations (Scopus)

Abstract

We have analyzed new and archival time series spectra taken six years apart during transits of the hot Jupiter WASP-33 b, and spectroscopically resolved the line profile perturbation caused by the Rossiter–McLaughlin effect. The motion of this line profile perturbation is determined by the path of the planet across the stellar disk, which we show to have changed between the two epochs due to nodal precession of the planetary orbit. We measured rates of change of the impact parameter and the sky-projected spin–orbit misalignment of db/dt = -0.0228+0.0050-0.0018 yr-1 and dλ/dt = -0º.373+0.089-0.076 yr-1, respectively, corresponding to a rate of nodal precession of dΩ/dt =-0º.373+0.031-0.083 yr-1. This is only the second measurement of nodal precession for a confirmed exoplanet transiting a single star. Finally, we used the rate of precession to set limits on the stellar gravitational quadrupole moment of 0.0054≤ J2 ≤ 0.035.

Original languageEnglish
JournalAstrophysical Journal Letters
Volume810
Issue number2
DOIs
Publication statusPublished - 3 Sept 2015

Keywords

  • Line: profiles
  • Planet–star interactions
  • Planetary systems
  • Planets and satellites: individual (WASP-33 b)
  • Techniques: spectroscopic

Fingerprint

Dive into the research topics of 'Measurement of the nodal precession of WASP-33 b via doppler tomography'. Together they form a unique fingerprint.

Cite this