The Complicated Wasp-47 Multi Exoplanet System With a hot Jupiter

Doppler Monitoring of the WASP-47 Multiplanet System

Authors:

Dai et al

Abstract:

We present precise Doppler observations of WASP-47, a transiting planetary system featuring a hot Jupiter with both inner and outer planetary companions. This system has an unusual architecture and also provides a rare opportunity to measure planet masses in two different ways: the Doppler method, and the analysis of transit-timing variations (TTV). Based on the new Doppler data, obtained with the Planet Finder Spectrograph on the Magellan/Clay 6.5m telescope, the mass of the hot Jupiter is 370±29 M⊕. This is consistent with the previous Doppler determination as well as the TTV determination. For the inner planet WASP-47e, the Doppler data lead to a mass of 12.2±3.7 M⊕, in agreement with the TTV-based upper limit of less than 22~M⊕ (95% confidence). For the outer planet WASP-47d, the Doppler mass constraint of 10.4±8.4 M⊕ is consistent with the TTV-based measurement of 15.2+6.7−7.6 M⊕.