› › A Measurement Of The Branching Fractions And Cp Asymmetries Of The Decays B U2192 K*






Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B{u2192}K(*)l+l-.

Author :

Publisher :

Page : 16 pages

File Size : 48,66 MB

Release : 2012

Category :

ISBN :

Get eBook

Book Description

In a sample of 471×106 BB¯ events collected with the BABAR detector at the PEP-II e+e- collider we study the rare decays B→K(*)l+l-, where l+l- is either e+e- or ?+?-. We report results on partial branching fractions and isospin asymmetries in seven bins of dilepton mass-squared. We further present CP and lepton-flavor asymmetries for dilepton masses below and above the J/? resonance. We find no evidence for CP or lepton-flavor violation. The partial branching fractions and isospin asymmetries are consistent with the Standard Model predictions and with results from other experiments.



Measurements of the Branching Fractions and CP Asymmetries of B -] D0_CP K Decays

Author :

Publisher :

Page : 8 pages

File Size : 47,3 MB

Release : 2006

Category :

ISBN :

Get eBook

Book Description

We present a study of the decay B− 2!D{sub (CP)}° K− and its charge conjugate, where D{sub (CP)}° is reconstructed in CP-even, CP-odd, and non-CP flavor eigenstates, based on a sample of 232 million [Upsilon](4S) 2!B{bar B} decays collected with the BABAR detector at the PEP-II ee− storage ring. We measure the partial-rate charge asymmetries AC{sub CP±} and the ratios R{sub CP±} of the B 2!D° K decay branching fractions as measured in CP± and non-CP D° decays: A{sub CP+} = 0.35 ± 0.13(stat) ± 0.04(syst), A{sub CP-} = -0.06 ± 0.13(stat) ± 0.04(syst), R{sub CP+} = 0.90 ± 0.12(stat) ± 0.04(syst), R{sub CP-} = 0.86 {+-} 0.10(stat) {+-} 0.05(syst).









Measurements of Branching Fractions and CP-Violating Asymmetries in B-Meson Decays to the Charmless Two-Body States K[sup 0]pi+, K-bar[sup 0]K[sup +], and K[sup 0]K-bar[sup 0].

Author :

Publisher :

Page : pages

File Size : 29,46 MB

Release : 2004

Category :

ISBN :

Get eBook

Book Description

The authors present preliminary measurements of the branching fraction and the CP-violating charge asymmetry in the B[sup +] --> K[sup 0][pi][sup +] decay, and a preliminary measurement of the branching fraction of the B[sup 0] --> K[sup 0][bar K][sup 0] decay. No evidence of direct CP violation in the B[sup +] --> K[sup 0][pi][sup +] mode is observed. The B[sup 0] --> K[sup 0][bar K][sup 0] measurement constitutes the first observation of this decay channel: the probability of obtaining the result assuming the null-signal hypothesis is 3.4 x 10[sup -6]. The authors have also searched for the B[sup +] --> [bar K][sup 0]K[sup +] decay and set an upper limit on its branching fraction at 2.35 x 10[sup -6] at the 90% C.L. The branching-fraction measurements reported here are consistent with previous measurements of the same quantities, but are extracted from a data sample larger by a factor of 2.6.



Measurements of Branching Fraction Ratios and CP-asymmetries in Suppressed B-2!D(2!K+[pi]- )K- and B-2!D(2!K+[pi]- )[pi]- Decays

Author :

Publisher :

Page : 8 pages

File Size : 27,13 MB

Release : 2011

Category :

ISBN :

Get eBook

Book Description

We report the first reconstruction in hadron collisions of the suppressed decays B-2!D(2!K+[pi]- )K- and B-2!D(2!K+[pi]- )[pi]- decays, sensitive to the CKM phase [gamma], using data from 7 fb-1 of integrated luminosity collected by the CDF II detector at the Tevatron collider. We reconstruct a signal for the B-2!D(2!K+[pi]- )K- suppressed mode with a significance of 3.2 standard deviations, and measure the ratios of the suppressed to favored branching fractions R(K) = [22.0 " 8.6(stat) " 2.6(syst)] x 10-3, R+(K) = [42.6 " 13.7(stat) " 2.8(syst)] x 10-3, R-(K) = [3.8 " 10.3(stat) " 2.7(syst)] x 10-3 as well as the direct CP-violating asymmetry A(K) = -0.82"0.44(stat)"0.09(syst) of this mode. Corresponding quantities for B- 2!D(2!K+[pi]- )[pi]- decay are also reported.