Level of magnetic activity as a function of the rotation period. Left: index of chromospheric emission S_CaII as a function of rotational period P_rot. The RGB and RC stars are represented in red and green, respectively, while red giants with an unidentified evolutionary stage are in blue. Black symbols correspond to non-oscillating red giants in close binaries. Gray dots indicate non-oscillating red giants with an ambiguous binary signal. Triangles and diamonds represent wide (P_orb > 150 d) and close (P_orb ≤ 150 d) binaries identified by Gaia DR3, respectively. The gray background indicates the distribution of S_CaII for inactive stars, where a darker shade corresponds to a larger number of stars. The gray line represents the best fit of S_CaII as a function of . Right: corresponding figure for S_ph as measured by Gaulme et al. (2020). It is a reproduction of Fig. 12 of Gaulme et al. (2020) adapted to the sample for which we measured S_CaII.