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arXiv · 0707.2533

Mixings of 4-quark components in light non-singlet scalar mesons in QCD sum rules

J. Sugiyama·T. Nakamura·N. Ishii·T. Nishikawa·M. Oka
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Abstract

Mixings of 4-quark components in the non-singlet scalar mesons are studied in the QCD sum rules. We propose a formulation to evaluate the cross correlators of q\bar q and qq\bar q \bar q operators and to define the mixings of different Fock states in the sum rule. It is applied to the non-singlet scalar mesons, a_0 and K_0^\ast. It is found that the 4-quark operators predict lower masses than the q\bar q operators and that the 4-quark states occupy about 70-90% of the lowest mass states.

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J. Sugiyama, T. Nakamura, N. Ishii, T. Nishikawa, M. Oka. 2007-07-17. Mixings of 4-quark components in light non-singlet scalar mesons in QCD sum rules. https://doi.org/10.1103/physrevd.76.114010

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