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arXiv · hep-ph/9412242

From Tetraquark to Hexaquark: A Systematic Study of Heavy Exotics in the Large $N_c$ Limit

Abstract

A systematic study of multiquark exotics with one or $N_c-1$ heavy quarks in the large $N_c$ limit is presented. By binding a chiral soliton to a heavy meson, either a normal $N_c$-quark baryon or an exotic $(N_c+2)$-quark baryon is obtained. By replacing the heavy quark with $N_c-1$ heavy antiquarks, exotic $(2N_c-2)$-quark and $2N_c$-quark mesons are obtained. When $N_c = 3$, they are just the normal triquark baryon $Qqq$, the exotic pentaquark baryon $Q\bar q\bar q\bar q\bar q$, tetraquark di-meson $\bar Q \bar Q qq$ and the hexaquark di-baryon $\bar Q \bar Q \bar q \bar q\ bar q \bar q$ respectively. Their stabilities and decays are also discussed. In particular, it is shown that the ``heavy to heavy'' semileptonic decays are described by the Isgur--Wise form factors of the normal baryons.

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BibTeXRIS

Chi-Keung Chow. 1994-12-05. From Tetraquark to Hexaquark: A Systematic Study of Heavy Exotics in the Large $N_c$ Limit. https://doi.org/10.1103/physrevd.51.6327

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