We have measured the electromagnetic form factor of the charged pion by direct scattering of 100-GeV/c π− from stationary electrons in a liquid-hydrogen target at Fermilab. The deviations from the pointlike pion-scattering cross section may be characterized by a root-mean-square charge radius for the pion of 〈rπ2〉12=0.56±0.04 F.
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