Résumé : π-p→π0n differential cross-sections have been measured in the region of small 4-momentum transfer at 40 GeV/c incident momentum. The experiment performed at the IHEP 70 GeV accelerator makes use of a hodoscope γ-spectrometer. The t- dependence of the cross-section points to a dominance of the spin-flip amplitude. © 1981 Springer-Verlag.