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Small size pentaquark in QCD sum rule approach

A. G. Oganesian
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Abstract

The analysis of the sum rules (for two differentchoices of 5-quark currents) indicate that to explain experimental results it is necessary to have some one-particle lower state (and pentaquark is a reliable candidate to this state) while the two-particle coupled lower state ($NK$ system) should be excluded. Obtained sum rules have good stability and correspond to pentaquark mass $m_θ$=1.54 $GeV$ at the appropriate choice of continuum threshold. Also the features of the sum rules for 2-point correlator with 5-quark currents are studied. This features should be taken into account to obtain sum rules correctly.

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A. G. Oganesian. 2005-10-26. Small size pentaquark in QCD sum rule approach. https://arxiv.org/abs/hep-ph/0510327

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