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arXiv · 0807.3275

The meson $Z^+(4430)$ as a tetraquark state

M. E. Bracco·S. H. Lee·M. Nielsen·R. Rodrigues da Silva
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Abstract

We test the validity of the QCD sum rules applied to the meson $Z^+(4430)$, by considering a diquark-antidiquark type of current with $J^{P}=0^{-}$ and with $J^{P}=1^{-}$. We find that, with the studied currents, it is possible to find an acceptable Borel window. In such a Borel window we have simultaneously a good OPE convergence and a pole contribution which is bigger than the continuum contribution. We get $m_Z=(4.52\pm0.09)\GeV$ and $m_Z=(4.84\pm0.14)\GeV$ for the currents with $J^{P}=0^{-}$ and $J^{P}=1^{-}$ respectively. We conclude that the QCD sum rules results favors $J^{P}=0^{-}$ quantum numbers for the $Z^+(4430)$ meson.

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M. E. Bracco, S. H. Lee, M. Nielsen, R. Rodrigues da Silva. 2008-12-16. The meson $Z^+(4430)$ as a tetraquark state. https://doi.org/10.1016/j.physletb.2008.12.021

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