We present a measurement of the W-boson polarization in top-quark decays in tt events with decays to dilepton final states using data corresponding to 5.1 fb-1 of integrated luminosity in pp collisions collected by the CDF II detector at the Tevatron. Assuming a top-quark mass of 172.5 GeV/c2, a simultaneous measurement of the fractions of longitudinal (f0) and right-handed (f+) W-bosons yields the results f0=0.70-0.17+0.18(stat)±0.06(syst) and f+=-0.09±0.09(stat)±0.03(syst). Combining this measurement with our previous measurement based on single-lepton final states, we obtain f0=0.84±0.09(stat)±0.05(syst) and f+=-0.16±0.05(stat)±0.04(syst). The results are consistent with the standard model expectation.
W-boson polarization measurement in the t(t)over-bar dilepton channel using the CDF II detector
Manca, G.;
2013-01-01
Abstract
We present a measurement of the W-boson polarization in top-quark decays in tt events with decays to dilepton final states using data corresponding to 5.1 fb-1 of integrated luminosity in pp collisions collected by the CDF II detector at the Tevatron. Assuming a top-quark mass of 172.5 GeV/c2, a simultaneous measurement of the fractions of longitudinal (f0) and right-handed (f+) W-bosons yields the results f0=0.70-0.17+0.18(stat)±0.06(syst) and f+=-0.09±0.09(stat)±0.03(syst). Combining this measurement with our previous measurement based on single-lepton final states, we obtain f0=0.84±0.09(stat)±0.05(syst) and f+=-0.16±0.05(stat)±0.04(syst). The results are consistent with the standard model expectation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.