2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/192255Results for d$σ$/d$Ω$ and $A_N$ in the reaction $\bar{p}p \rightarrow π^- π^+$ are predicted by a simple quark model. They are compared to recent experimental data from LEAR, as well as to previous predictions from nucleon-exchange models. At low energy the quark model does better than the nucleon-exchange models, but the overall comparison to experiment remains poor. In particular, the double-dip structure of the experimental $A_N$ data is only partly represented. This shortcoming of the simple quark model is traced back to a too small J=2 amplitude. This has interesting implications for the range of this specific annihilation process.LATEX, 11 pages, 6 figures (available upon request), #RU9305Nuclear Theorytext