Electroproduction of the Delta Resonance at High Momentum Transfer

Abstract

We studied the electroproduction of the Delta(1232) resonance via the reaction p(e,e'p)\pi0 at four-momentum transfers Qsq = 2.8 and 4.0 GeV^2. This is the highest Qsq for which exclusive resonance electroproduction has ever been observed. Decay angular distributions for Delta to p-pi0$weremeasuredoverawiderangeofbarycentricenergiescoveringtheresonance.The$N-Δ$ transition form factor G*_M and ratios of resonant multipoles E{1+}/M{1+} and S{1+}/M{1+} were extracted from the decay angular distributions. These ratios remain small, indicating that perturbative QCD is not applicable for this reaction at these momentum transfers.

5 pages, 3 figures

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Cited by in corpus (130)

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