Hard Exclusive Electroproduction of Two Pions off Proton and Deuteron at HERMES
نویسندگان
چکیده
Exclusive electroproduction of π+π− pairs off hydrogen and deuterium targets has been studied with the HERMES experiment. The angular distribution of the π+ in the π+π− rest system has been studied in the invariant mass range 0.3 < mππ < 1.5 GeV. Theoretical models derived in the framework of the Generalized Parton Distributions show that this angular distribution receives only contributions from the interference between the isoscalar channel I = 0 and the isovector channel I = 1.
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