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Description
We report the discovery of two additional planetary companions to WASP-41 and WASP-47. WASP-41c is a planet of minimum mass 3.18+/-0.20M_Jup_ and eccentricity 0.29+/-0.02, and it orbits in 421+/-2-days. WASP-47c is a planet of minimum mass 1.24+/-0.22M_Jup_ and eccentricity 0.13+/-0.10, and it orbits in 572+/-7-days. Unlike most of the planetary systems that include a hot Jupiter, these two systems with a hot Jupiter have a long-period planet located at only about 1AU from their host star. WASP-41 is a rather young star known to be chromospherically active. To differentiate its magnetic cycle from the radial velocity effect induced by the second planet, we used the emission in the Halpha line and find this indicator well suited to detecting the stellar activity pattern and the magnetic cycle. The analysis of the Rossiter-McLaughlin effect induced by WASP-41b suggests that the planet could be misaligned, though an aligned orbit cannot be excluded. WASP-47 has recently been found to host two additional transiting super Earths. With such an unprecedented architecture, the WASP-47 system will be very important for understanding planetary migration.
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