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تسجيل مستخدم جديدEvidence for a new $Sigma^{*}$ resonance with $J^P=1/2^-$ in the old data of $K^-ptoLambdapi^+pi^-$ reaction
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Distinctive patterns are predicted by quenched quark models and unquenched quark models for the lowest SU(3) baryon nonet with spin parity $J^P=1/2^-$. While the quenched quark models predict the lowest $1/2^-$ $Sigma^*$ resonance to be above 1600 MeV, the unquenched quark models predict it to be around $Sigma^*(1385)$ energy. Here we re-examine some old data of the $kp to la$ reaction and find that besides the well established $Sigma^{*}(1385)$ with $J^P=3/2^+$, there is indeed some evidence for the possible existence of a new $Sigma^{*}$ resonance with $J^P=1/2^-$ around the same mass but with broader decay width. Higher statistic data on relevant reactions are needed to clarify the situation.
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The unquenched quark models predict the new particle $Sigma^*$ with spin parity $J^P=1/2^-$ and its mass is around the well established $Sigma^*(1385)$ with $J^P=3/2^+$. Here by using the effective Lagrangian approach we study kp reaction at the rang
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