Comparison of [hs/ls] and upper limit on [Pb/hs] for HD 20 against AGB s-process models of different initial masses. The value determined for HD 20 is indicated by blue horizontal lines and error margins, while models of Z = 0.0001 without rotation are shown in red. The adopted best-fit model with a rotation of 30 km s⁻¹ is depicted in orange. For juxtaposition, we show i-process predictions for [hs/ls] from Hampel et al. (2016) for four different neutron densities, n_i, in the upper panel using black dotted, dash-dotted, dashed, and solid lines (see legend).