اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدStudy of the near-threshold $omegaphi$ mass enhancement in doubly OZI suppressed $J/psi to gammaomegaphi$ decays
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A 2.25$times10^8$ $jpsi$ event sample accumulated with the BESIII detector is used to study the doubly OZI suppressed decay modes $jpsitogammaof$, $omegatoppp$, $phitokk$. A strong deviation ($>$ 30$sigma$) from three-body $jpsitogammaomegaphi$ phase space is observed near the $omegaphi$ mass threshold that is consistent with a previous observation reported by the BESII experiment. A partial wave analysis with a tensor covariant amplitude that assumes that the enhancement is due to the presence of a resonance, the X(1810), is performed, and confirms that the spin-parity of the X(1810) is $0^{++}$. The mass and width of the X(1810) are determined to be $M=1795pm7$(stat)$^{+13}_{-5}$(syst)$pm$19(mod) MeV/$c^2$ and $Gamma=95pm10$(stat)$^{+21}_{-34}$(syst)$pm$75(mod) MeV/$c^2$, respectively, and the product branching fraction is measured to be ${cal B}(jpsitogamma X(1810))times{cal B}(X(1810)toof)=(2.00pm0.08$(stat)$^{+0.45}_{-1.00}$(syst)$pm$1.30(mod))$times10^{-4}$. %where the first error is the statistical error and the second the systematical error. These results are consistent within errors with those of the BESII experiment.
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