اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدResonances and $CP$ violation in $B_s^0$ and $overline{B}_s^0 to J/psi K^+K^-$ decays in the mass region above the $phi(1020)$
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The decays of $B_s^0$ and $overline{B}_s^0$ mesons into the $J/psi K^+K^-$ final state are studied in the $K^+K^-$ mass region above the $phi(1020)$ meson in order to determine the resonant substructure and measure the $CP$-violating phase, $phi_s$, the decay width, $Gamma_s$, and the width difference between light and heavy mass eigenstates, $DeltaGamma_s$. A decay-time dependent amplitude analysis is employed. The data sample corresponds to an integrated luminosity of $3{rm fb}^{-1}$ produced in 7 and 8 Tev $pp$ collisions at the LHC, collected by the LHCb experiment. The measurement determines $phi_s = 119pm107pm34 {rm , mrad}$. A combination with previous LHCb measurements using similar decays into the $J/psi pi^+pi^-$ and $J/psiphi(1020)$ final states gives $phi_s=1pm37 {rm ,mrad}$, consistent with the Standard Model prediction.
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