Seismic diagram of the 372 red giants studied in this work, with used as a proxy for the luminosity. The color codes the stellar mass. Stars on the RGB are plotted with + symbols, red clump stars with ⋄. The dotted and dashed lines indicate the limit of the visibility of mixed modes for RGB and clump stars, respectively, as defined by Eq. (31). Evolution tracks on the RGB, computed with MESA for solar metallicity (Gehan et al. 2018), are shown for the stellar masses 1.0, 1.3, 1.6, and 1.9 M_⊙. The error box indicates the typical 1-σ uncertainties on T_eff and ν_max.