Exclusive high-Q² electroproduction: light-cone wave functions and electromagnetic form factors of mesons,

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We apply the light-cone technique to electroproduction reaction ep→ eπ+n long considered as a means of measuring the electromagnetic form factor of the pion. We show that the interpretation of the long-standing puzzle of large transverse cross section (σₜ) in terms of the γ*ρ→ π transition on the ρ mesons in the light-cone proton is possible, but requires quite a slow decrease of the Fᵨπ(2) form factor. This interpretation can be tested in the related ep→ eπ⁰p reaction. Corrections which are due to the final-state meson-baryon interactions (FSI) are evaluated and are shown to amount to a 25% effect at moderately large 2. Vanishing FSI with increasing Q² - the color transparency phenomenon - is shown to be very strong.