اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of the CP-violating phase $phi_s$ in $bar{B}^{0}_{s}to D_{s}^{+}D_{s}^{-}$ decays
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We present a measurement of the $CP$-violating weak mixing phase $phi_s$ using the decay $bar{B}^{0}_{s}to D_{s}^{+}D_{s}^{-}$ in a data sample corresponding to $3.0$ fb$^{-1}$ of integrated luminosity collected with the LHCb detector in $pp$ collisions at centre-of-mass energies of 7 and 8 TeV. An analysis of the time evolution of the system, which does not constrain $|lambda|=1$ to allow for the presence of $CP$ violation in decay, yields $phi_s = 0.02 pm 0.17$ (stat) $pm 0.02$ (syst) rad, $|lambda| = 0.91^{+0.18}_{-0.15}$ (stat) $pm0.02$ (syst). This result is consistent with the Standard Model expectation.
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nt amplitude analysis is used to determine the final-state resonance contributions, the $CP$-violating phase $phi_s=-0.057pm 0.060pm 0.011$ rad, the decay-width difference between the heavier mass $B_{s}^{0}$ eigenstate and the $B^{0}$ meson of $-0.050pm 0.004pm 0.004$ ps$^{-1}$, and the $CP$-violating parameter $|lambda|=1.01_{-0.06}^{+0.08}pm0.03$, where the first uncertainty is statistical and the second systematic. These results are combined with previous LHCb measurements in the same decay channel using 7 TeV and 8 TeV $pp$ collisions obtaining $phi_s =0.002pm0.044pm0.012$ rad, and $|lambda| =0.949pm0.036pm0.019$.
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