The role of five-quark components in gamma decay of the Δ(1232)

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An admixture of 10-20 % of qqqq q components in the Delta(1232) resonance is shown to reduce the well known underprediction for the decay width for Delta(1232)->N gamma decay by about half and that of the corresponding helicity amplitudes from a factor 1.7 to 1.5. The main effect is due to the quark-antiquark annihilation transitions qqqq q -> qqq gamma, the consideration of which brings the ratio A₃/₂/A₁/₂ and consequently the E2/M1 ratio REM into agreement with the empirical value. Transitions between qqqq q components in the resonance and the nucleon qqqq q->qqqq q gamma are shown to enhance the calculated width by only a few percent, as long as the probability of the qqqq q component of the Delta(1232) and the proton is at most 20 %. The transitions qqqq q->qqqq q gamma between the qqqq q components in the Delta(1232) and the proton do not lead to a nonzero value for REM.