اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدEvidence for a vector charmonium-like state in $e^+e^- to D^+_sD^*_{s2}(2573)^-+c.c.$
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We report the measurement of $e^+e^- to D^+_sD^*_{s2}(2573)^-+c.c.$ via initial-state radiation using a data sample of an integrated luminosity of 921.9 fb$^{-1}$ collected with the Belle detector at the $Upsilon(4S)$ and nearby. We find evidence for an enhancement with a 3.4$sigma$ significance in the invariant mass of $D^+_sD^*_{s2}(2573)^- +c.c.$ The measured mass and width are $(4619.8^{+8.9}_{-8.0}({rm stat.})pm2.3({rm syst.}))~{rm MeV}/c^{2}$ and $(47.0^{+31.3}_{-14.8}({rm stat.})pm4.6({rm syst.}))~{rm MeV}$, respectively. The mass, width, and quantum numbers of this enhancement are consistent with the charmonium-like state at 4626 MeV/$c^2$ recently reported by Belle in $e^+e^-to D^+_sD_{s1}(2536)^-+c.c.$ The product of the $e^+e^-to D^+_sD^*_{s2}(2573)^-+c.c.$ cross section and the branching fraction of $D^*_{s2}(2573)^-to{bar D}^0K^-$ is measured from $D^+_sD^*_{s2}(2573)^-$ threshold to 5.6 GeV.
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Using a data sample of 921.9 fb$^{-1}$ collected with the Belle detector, we study the process of $e^+e^-to D^+_sD_{s1}(2536)^-+c.c.$ via initial-state radiation. We report the first observation of a vector charmoniumlike state decaying to $D^+_sD_{s
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