Left: profiles of the Lamb frequencies (S_l; red lines) for l = {1,2} and of the Brunt-Väisälä frequency (N; blue line) for the studied 1.5M_⊙ 2.8 Gyr old intermediate-mass red giant star (with a solar metallicity Z = 0.02); the position of ν_max is also reported (orange line). Right: topology of the fossil magnetic field in the stably stratified radiative core of the studied red giant (its limit is given by the thick black line). The thin black lines are the poloidal field lines, while the intensity of the toroidal field (normalised by the maximum values of the radial field) is given in colours.