Description
We report the discovery of a system of two super-Earths orbiting the moderately active K-dwarf HD 176986. This work is part of the RoPES RV program of G- and K-type stars that combines radial velocity from both HARPS and HARPS-N spectrograph to search for short-period terrestrial planets. HD 176986 b and c are super-Earth mass planets with masses of 5.74 and 9.18 Me, with orbital periods of 6.49 and 16.82 days, at a distances of 0.063 and 0.119AU, in orbits that are consistent with circular. The host star is a K2.5 dwarf, and in spite of its modest level of chromospheric activity log(R'hk)=-4.90+/-0.04, shows a complex activity pattern. Along with the discovery of the planets we study the magnetic cycle and rotation of the star. HD 176986 proves to be suitable to test the available techniques of RV analysis and our understanding of stellar activity.
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