Resulting [Rb/Fe] and [Zr/Fe] for low-metallicity intermediate-mass AGB models indicated by the labels. For comparison we included the 5 M_⊙Z = 0.02 model. As in Fig. 3 the solid part of the lines are equivalent to λ = 0 during the extended evolution. The dashed lines are the result of the synthetic extension when the TDU efficiency is chosen to remain constant. The observed [Rb/Fe] in five Rb-rich stars in the Magellanic Clouds ranges from  + 1.7 dex to  + 5.0 dex, outside of the range of the figure. (This figure is available in color in the electronic form.)