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Does A Narrow Tetraquark $cc\bar{u}\bar{d}$ State Exist?

Boris A. Gelman·Shmuel Nussinov
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Abstract

The existence of a shallow or virtual tetraquark state, $cc\bar{u}\bar{d}$, is discussed. Using the putative masses for the doubly charmed baryons ($ccu/ccd$) from SELEX, the mass of the $cc\bar{u}\bar{d}$ state is estimated to be about $3.9 GeV$, only slightly above the $DD^*$ threshold. The experimental signatures for various $cc\bar{u}\bar{d}$ masses are also discussed.

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Boris A. Gelman, Shmuel Nussinov. 2002-11-07. Does A Narrow Tetraquark $cc\bar{u}\bar{d}$ State Exist?. https://doi.org/10.1016/s0370-2693(02)03069-1

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