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Hard diffractive electroproduction of two pions

B. Lehmann-Dronke·P. V. Pobylitsa·M. V. Polyakov·A. Schafer·K. Goeke
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Abstract

We have calculated the leading order amplitude of hard diffractive electroproduction of two pions in lepton nucleon scattering. At the leading twist level a pion pair can be produced only in an isospin one or zero state. We have shown that isoscalar states are produced dominantly for x_{Bj}>0.3 and with an invariant mass of the two pions close to the threshold (S-wave) and in the f_2 resonance region (D-wave). These isoscalar pion pairs are dominantly produced by two collinear gluons. Comparing the production of charged and neutral pion pairs as a function of x_{Bj} and m_pipi one can get information about the gluonic component of two-pion distribution amplitudes.

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B. Lehmann-Dronke, P. V. Pobylitsa, M. V. Polyakov, A. Schafer, K. Goeke. 2000-02-20. Hard diffractive electroproduction of two pions. https://doi.org/10.1016/s0370-2693(00)00069-1

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