1 99 9 Multiquark picture for Σ ( 1620 )

In this work we report on a new QCD sum rule analysis to predict masses of the excited baryon states (e.g. Σ (1620) and Λ (1405)) by using multiquark interpolating fields ((qq̄)(qqq)). For the Σ (1620) we consider the K̄N , πΣ, and πΛ (I=1) multiquark interpolating fields. The calculated mass from those multiquark states is about 1.592 GeV. For the Λ (1405) we first show the result using the π+Σ− + π0Σ0 + π−Σ+ (I=0) multiquark interpolating field, and compare the calculated mass to that of our previous result using the π0Σ0 multiquark state. We then show that the mass 1.405 GeV is well reproduced when using the K̄N (I=0) multiquark state. The uncertainties in our sum rules are also discussed. PACS numbers: 24.85.+p, 14.20.-c, 21.10.Dr Typeset using REVTEX ∗Present address : Dept. of Physical Sciences, Hiroshima University, Higashi-Hiroshima 739-8526, Japan (e-mail : [email protected]).