اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدCoupled-Channel-Induced $S-D$ mixing of Charmonia and Testing Possible Assignments for $Y(4260)$ and $Y(4360)$
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The mass spectrum and the two-body open-charm decays of the $J^{PC}=1^{--}$ charmonium states are studied with the coupled-channel effects taken into account. The coupled-channel-induced mixing effects among the excited vector charmonia are studied. Based on our calculations of the masses and the decay widths, we find that the tension between the observed properties of $Y(4260)/Y(4360)$ and their conventional charmonia interpretations could be softened.
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We report the results of a search for the $B to Y(4260) K, ~Y(4260)to J/psipi^+pi^-$ decays. This study is based on a data sample corresponding to an integrated luminosity of 711~fb$^{-1}$, collected at the $Upsilon(4S)$ resonance with the Belle dete
ctor at the KEKB asymmetric-energy $e^+ e^-$ collider. We investigate the $J/psipi^+pi^-$ invariant mass distribution in the range 4.0 to 4.6 GeV/$c^2$ using both $B^+ to J/psi pi^+pi^- K^+$ and $B^0 to J/psi pi^+pi^- K^0_S$ decays. We find excesses of events above the background levels, with a significances of 2.1 and 0.9 standard deviations for charged and neutral $B to Y(4260) K$ decays, respectively, taking into account the systematic uncertainties. These correspond to upper limits on the product of branching fractions, ${cal B}(B^+ to Y(4260) K^+) times {cal B}(Y(4260) to J/psi pi^+ pi^-) <1.4 times 10^{-5}$ and ${cal B}(B^0 to Y(4260) K^0) times {cal B}(Y(4260) to J/psi pi^+ pi^-) <1.7 times 10^{-5}$ at the 90% confidence level.
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st frame. Our results confirm our previous conclusions drawn from the magnitudes of vector-meson leptonic decay constants, identifying the Psi(3770) and Psi(4160) as D-wave states in our setup.
We study the processes $e^+ e^- to Y(4260) to J/psi pipi(Kbar{K})$. The strong final-state interactions, especially the coupled-channel ($pipi$ and $Kbar{K}$) final-state interaction in the $S$-wave are taken into account in a model-independent way u
sing dispersion theory. It is found that the light-quark SU(3) octet state plays a significant role in these transitions, implying that the $Y(4260)$ contains a large light-quark component. Our findings suggest that the $Y(4260)$ is neither a hybrid nor a conventional charmonium state. Furthermore, through an analysis of the ratio of the light-quark SU(3) octet and singlet components, we show that the $Y(4260)$ does not behave like a pure $bar D D_1$ hadronic molecule as well.
The $Y(4260)$ has been one of the most puzzling pieces among the so-called $XYZ$ states. In this paper, we try to gain insights into the structure of the $Y(4260)$ from the light-quark perspective. We study the dipion invariant mass spectrum of the $
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The cross sections of the process $e^{+}e^{-} to eta J/psi$ at center-of-mass energies ($sqrt{s}$) between 3.81 and 4.60 GeV are measured with high precision by using data samples collected with the BESIII detector operating at the BEPCII storage rin
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