Is $d^*$ a candidate of hexaquark-dominated exotic state?

F. Huang; Z. Y. Zhang; P. N. Shen; W. L. Wang

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arXiv · 1408.0458

Is $d^*$ a candidate of hexaquark-dominated exotic state?

F. Huang·Z. Y. Zhang·P. N. Shen·W. L. Wang

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Abstract

We confirm our previous prediction of a $d^*$ state with $I(J^P)=0(3^+)$ [Phys. Rev. C 60, 045203 (1999)] and report for the first time based on a microscopic calculation that $d^*$ is a hexaquark dominated exotic state as it has about 2/3 hidden color (CC) configurations. By performing a more elaborate dynamical coupled-channels investigation of the $\Delta\Delta$-CC system within the framework of resonating group method (RGM) in a chiral quark model, we found that the $d^*$ state has a mass of about 2.38-2.42 GeV, a root-mean-square radius (RMS) of 0.76-0.88 fm, and a CC fraction of 66%-68%. The last ensures that the $d^*$ has a rather narrow width which, together with the quantum numbers and our calculated mass, is consistent with the newly observed resonance-like structure ($M\approx 2380$ MeV, $\Gamma\approx 70$ MeV) in double-pionic fusion reactions reported by WASA-at-COSY Collaboration.

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F. Huang, Z. Y. Zhang, P. N. Shen, W. L. Wang. 2014-08-03. Is $d^*$ a candidate of hexaquark-dominated exotic state?. https://arxiv.org/abs/1408.0458

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