The electroproduction of the ∆(1232) in the chiral quark-soliton model
نویسندگان
چکیده
We calculate the ratios E2/M1 and C2/M1 for the electroproduction of the ∆(1232) in the region of photon virtuality 0<−q2 < 1 GeV. The magnetic dipole amplitude M1 is also presented. The theory used is the chiral quark-soliton model, which is based on the instanton vacuum of the QCD. The calculations are performed in flavours SU(2) and SU(3) taking rotational (1/Nc) corrections into account. The results for the ratios agree qualitatively with the available data, although the magnitude of both ratios seems to underestimate the latest experimental results. PACS numbers: 12.39Fe; 13.40-f; 14.20-c
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تاریخ انتشار 1999