Values of the coupling strength q computed in the three ways presented in Sect. 3 as a function of ν_max for stellar models with M = 1.25 M_⊙,  Z = 0.020 along the RGB. The star evolves from right to left. The solid lines represent q_w(ν_max) (dark blue for the full profile, and light blue for profile without the N² spike) and q_s(ν_max) (red for the full profile, and purple without the spike), and the shaded areas show the range of values we calculated for the frequencies in the sample used for the fit. The green markers show q_as with the uncertainties as described in Sect. 3.3. Below 100 μHz, the x-axis ticks show spacings of 10 μHz; above 100 μHz, the major ticks show spacings of 100 μHz and the minor ticks continue in steps of 10 μHz. The arrow indicates the model that is further analyzed in Fig. 10.