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تسجيل مستخدم جديد$Upsilon(nl)$ decay into $ B^{(*)} bar B^{(*)}$
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We have evaluated the decay modes of the $Upsilon(4s), Upsilon(3d), Upsilon(5s), Upsilon(6s)$ states into $Bbar B, Bbar B^*+c.c., B^* bar B^*, B_s bar B_s, B_s bar B^*_s +c.c., B^*_s bar B_s^* $ using the $^3P_0$ model to hadronize the $bbar b$ vector seed, fitting some parameters to the data. We observe that the $Upsilon(4s)$ state has an abnormally large amount of meson-meson components in the wave function, while the other states are largely $bbar b$. We predict branching ratios for the different decay channels which can be contrasted with experiment for the case of the $Upsilon(5s)$ state. While globally the agreement is fair, we call the attention to some disagreement that could be a warning for the existence of more elaborate components in the state.
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