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تسجيل مستخدم جديدObservation of candidate exotic mesons containing heavy quarks with Belle
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S.-K.Choi
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We report the observation of two resonance-like structures in the $pi^+ chi_{c1}$ invariant mass distribution near 4.1 GeV in exclusive $Bto Kpi^+chi_{c1}$ decays. A detailed Dalitz-plot analysis demonstrates that these structures cannot be produced by reflections from any known and possibly unknown resonances in the $Kpi$ channel. If these two peaks are produced by resonances in the $pi^+chi_{c1}$ channel, their minimal quark structure would have to be a $cbar{c}ubar{d}$ tetraquark arrangement, similar to that proposed for the $Z^+(4430)$ structure reported by Belle last year in the $pi^+psi^{}$ mass distribution produced in $Bto Kpi^+psi^{}$ decays. In addition, we report some new measurements on the properties of the X(3872) meson and the $1^{--}$ $Y$ states that are produced with initial state radiation. %and also other latest XYZ results. The analyses are based on a large data sample recorded at the $Upsilon(4S)$ resonances and nearby continuum with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider.
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