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تسجيل مستخدم جديدFive-quark components in baryons
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B.S.Zou
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Evidence has been accumulating for the existence of significant intrinsic non-perturbative five-quark components in various baryons. The inclusion of the five-quark components gives a natural explanation of the excess of $bar d$ over $bar u$, significant quark orbital angular momentum in the proton, the problematic mass and decay pattern of the lowest $1/2^-$ baryon nonet, etc.. A breathing mode of $qqqleftrightarrow qqqqbar q$ is suggested for the lowest $1/2^-$ baryon octet. Evidence of a predicted member of the new scheme, $Sigma^*(1/2^-)$ around 1380 MeV, is introduced.
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