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arXiv · 1504.02631

Observation of the first iso-spin Charmonium-like State $Z_c(4020)$ }

Qing-Ping Ji·Yu-Ping Guo·Ai-Qiang Guo·Chun-Xu Yu·Zhi-Yong Wang
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Abstract

In this paper, we present a new experimental progress in brief on the recent observation of the charged charmonium-like state Z_c(4020)^{+/-} states and its iso-spin partner Z_c(4020)^{0} in pi pi hc process at the BESIII experiment. The charged Z_{c}(4020) is its decay into π^{+/-} hc final state, and carries electric charge, thus it contains at least four quarks. The observation of both charge and neutral state makes Z_{c}(4020) the first iso-spin triplet Z_{c} state observed in experiment.

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Qing-Ping Ji, Yu-Ping Guo, Ai-Qiang Guo, Chun-Xu Yu, Zhi-Yong Wang. 2015-04-10. Observation of the first iso-spin Charmonium-like State $Z_c(4020)$ }. https://doi.org/10.1088/1674-1137%2F40%2F1%2F012001

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