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arXiv · hep-ph/0608316

Dynamical study of ${\bf QQ-\bar u \bar d}$ mesons

Abstract

It has been recently conjectured by Selem and Wilczek \cite{Sel06} the existence of a $ss-[\bar u \bar d]$ meson due to strong correlations between the two light antiquarks. We make a detailed study of this system within a dynamical quark model which has proven to be successful in reproducing the most important features of low-energy hadron phenomenology. Our results, obtained within a parameter-free calculation, show that the antidiquark component of the $ss \bar u \bar d$ system indeed entails the stronger attraction, and drives its energy much lower than the $\bar{N}Ξ$ threshold, but still above the $\bar{K^0} {K^*}^-$ or $\bar{{K^*}^0} K^-$ thresholds. We have also studied the $cc \bar u \bar d$ and $bb \bar u \bar d$ systems. Exotic mesons are only expected to exist in the limit of large mass for the two-quark subsystem, $bb\bar u \bar d$, since the calculated mass is below the $\bar{B^0} {B^*}^-$ or $\bar{{B^*}^0} B^-$ thresholds.

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BibTeXRIS

J. Vijande, A. Valcarce, K. Tsushima. 2006-08-30. Dynamical study of ${\bf QQ-\bar u \bar d}$ mesons. https://doi.org/10.1103/physrevd.74.054018

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