We present the first precise measurement of the Bs0-B̅ s0 oscillation frequency Δms. We use 1 fb-1 of data from pp̅ collisions at √s=1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. The sample contains signals of 3600 fully reconstructed hadronic Bs decays and 37 000 partially reconstructed semileptonic Bs decays. We measure the probability as a function of proper decay time that the Bs decays with the same, or opposite, flavor as the flavor at production, and we find a signal consistent with Bs0-B̅ s0 oscillations. The probability that random fluctuations could produce a comparable signal is 0.2%. Under the hypothesis that the signal is due to Bs0-B̅ s0 oscillations, we measure Δms=17.31-0.18+0.33(stat)±0.07(syst) ps-1 and determine |Vtd/Vts|=0.208-0.002+0.001(expt)-0.006+0.008(theor).
Measurement of the Bs0-B̅ s0 Oscillation Frequency
PAGLIARONE, Carmine Elvezio;
2006-01-01
Abstract
We present the first precise measurement of the Bs0-B̅ s0 oscillation frequency Δms. We use 1 fb-1 of data from pp̅ collisions at √s=1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. The sample contains signals of 3600 fully reconstructed hadronic Bs decays and 37 000 partially reconstructed semileptonic Bs decays. We measure the probability as a function of proper decay time that the Bs decays with the same, or opposite, flavor as the flavor at production, and we find a signal consistent with Bs0-B̅ s0 oscillations. The probability that random fluctuations could produce a comparable signal is 0.2%. Under the hypothesis that the signal is due to Bs0-B̅ s0 oscillations, we measure Δms=17.31-0.18+0.33(stat)±0.07(syst) ps-1 and determine |Vtd/Vts|=0.208-0.002+0.001(expt)-0.006+0.008(theor).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
