The cross section for the process e + e − → π + π − is measured in the c.m. energy range 1.04—1.38 GeV by analyzing 995 000 selected collinear events including 860000 e + e − events, 82000 μ + μ − events, and 33000 π + π − events. The systematic and statistical errors of measuring the pion form factor are equal to 1.2–4.2 and 5–13%, respectively.
No takes yet. Share an insight, caveat, or question.
Aulchenko et al. (2005) studied this question.
Synapse has enriched one closely related paper. Consider it for comparative context: