اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدObservation of an alternative $chi_{c0}(2P)$ candidate in $e^+ e^- rightarrow J/psi D bar{D}$
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We perform a full amplitude analysis of the process $e^+ e^- rightarrow J/psi D bar{D}$, where $D$ refers to either $D^0$ or $D^+$. A new charmoniumlike state $X^*(3860)$ that decays to $D bar{D}$ is observed with a significance of $6.5sigma$. Its mass is ($3862^{+26}_{-32}{}^{+40}_{-13}$) MeV/$c^2$ and width is ($201^{+154}_{-67}{}^{+88}_{-82}$) MeV. The $J^{PC}=0^{++}$ hypothesis is favored over the $2^{++}$ hypothesis at the level of $2.5sigma$. The analysis is based on the 980 $mathrm{fb}^{-1}$ data sample collected by the Belle detector at the asymmetric-energy $e^+ e^-$ collider KEKB.
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Using $4.479 times 10^{8}$ $psi(3686)$ events collected with the BESIII detector, we search for the decays $psi(3686) rightarrow e^{+}e^{-}chi_{c0,1,2}$ and $chi_{c0,1,2} rightarrow e^{+}e^{-}J/psi$. The decays $psi(3686) rightarrow e^{+}e^{-}chi_{c0
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