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Five-quark components in $Δ(1232)\to Nπ$ decay

Q. B. Li·D. O. Riska
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Abstract

Five-quark $qqqq\bar q$ components in the $Δ(1232)$ are shown to contribute significantly to $Δ(1232)\to Nπ$ decay through quark-antiquark annihilation transitions. These involve the overlap between the $qqq$ and $qqqq\bar q$ components and may be triggered by the confining interaction between the quarks. With a $\sim$ 10% admixture of five-quark components in the $Δ(1232)$ the decay width can be larger by factors 2 - 3 over that calculated in the quark model with 3 valence quarks, depending on the details of the confining interaction. The effect of transitions between the $qqqq\bar q$ components themselves on the calculated decay width is however small. The large contribution of the quark-antiquark annihilation transitions thus may compensate the underprediction of the width of the $Δ(1232)$ by the valence quark model, once the $Δ(1232)$ contains $qqqq\bar q$ components with $\sim$ 10% probability.

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Q. B. Li, D. O. Riska. 2006-02-02. Five-quark components in $Δ(1232)\to Nπ$ decay. https://doi.org/10.1103/physrevc.73.035201

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