Values of ω^* for each Ba star as a function of the residuals Δ [Nb/Fe]. The grey crosses represent the points calculated from the Ba star abundances. The coloured points correspond to the data recalculated to the AGB values, colour-coded to the value of the residual, with the same scale is in Fig. 15. The fitted line is to the AGB values, the r_S coefficient and the slope a of the fitted line to this relation are shown above. The same fit for the Ba star abundances gives r_S = −0.74 and a = −15.38.