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Probing an axial-vector tetraquark $Z_s$ via its semileptonic decay $Z_s to X(4274)overline{l} u_l$

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 نشر من قبل Kazem Azizi
 تاريخ النشر 2018
  مجال البحث
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The semileptonic decays of the open charm-bottom axial-vector tetraquark $ Z_{s}=[cs][overline{b}overline{s}]$ to $X(4274)overline{l} u_l$, $l=e, mu, tau $ are explored by means of the QCD three-point sum rule method. Both $Z_{s}$ and $X(4274)=[cs][overline{c}overline{s}]$ are treated as color sextet diquark-antidiquark states. The full width of the decays $Z_s to X(4274)overline{l} u_l$ is found. Obtained predictions for $ Gamma(Z_s to X(4274)overline{l} u_l)$ demonstrate that, as in the case of the conventional hadrons, the semileptonic transitions form a very small part of its full width.

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