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arXiv · 1608.00238

Constituent counting rule for exclusive production of heavy quarkoniumlike exotic resonance and a light hadron

M. B. Voloshin
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Abstract

The exclusive processes are considered, where a point-like source of heavy quark-antiquark pairs $Q \bar Q$, e.g. their electromagnetic current, produces a pair consisting of a heavy quarkoniumlike exotic meson (tetraquark) or baryon (pentaquark) and a light meson or an antibaryon. For a sufficiently large mass of the heavy quark $m_Q$ there is a range of the energy $E$ above the $Q \bar Q$ threshold, where $E \ll m_Q$ and still the energy is large compared to the strong interaction scale, $E \gg \Lambda_{QCD}$. It is shown that in this energy range, where the heavy quarks are nonrelelativistic, a specific `intermediate asymptotic' behavior sets in determined by the number $n$ of the pairs of constituent quarks, with the rate scaling as $E^{1-n}$.

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M. B. Voloshin. 2016-07-31. Constituent counting rule for exclusive production of heavy quarkoniumlike exotic resonance and a light hadron. https://doi.org/10.1103/physrevd.94.074042

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