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تسجيل مستخدم جديدA QCD sum rule calculation for the Y(4140) narrow structure
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We use the QCD sum rules to evaluate the mass of a possible scalar mesonic state that couples to a molecular $D_{s}^{*}bar{D}_s^{*}$ current. We find a mass $m_{D_s^*D_s^*}=(4.14pm 0.09)$ GeV, which is in a excellent agreement with the recently observed Y(4140) charmonium state. We consider the contributions of condensates up to dimension eight, we work at leading order in $alpha_s$ and we keep terms which are linear in the strange quark mass $m_s$. We also consider a molecular $D^{*}bar{D}^{*}$ current and we obtain $m_{D^*{D}^*}=(4.13pm 0.10)$, around 200 MeV above the mass of the Y(3930) charmonium state. We conclude that it is possible to describe the Y(4140) structure as a $D_s^*bar{D}_s^*$ molecular state.
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