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تسجيل مستخدم جديدGenerating a resonance-like structure in the reaction $B_cto B_s pipi$
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We investigate the process $B_c^+to B_s^0pi^+pi^0$ via $Bbar{K}^*$ rescattering. The kinematic conditions for triangle singularities are perfectly satisfied in the rescattering diagrams. A resonance-like structure around the $Bbar{K}$ threshold, which we denote as $X(5777)$, is predicted to be present in the invariant mass distribution of $B_s^0 pi^+$. Because the relative weak $Bbar{K}$ $(I=1)$ interaction does not support the existence of a dynamically generated hadronic molecule, the $X(5777)$ can be identified as a pure kinematical effect due to the triangle singularity. Its observation may help to establish a non-resonance interpretation for some $XYZ$ particles.
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