相关论文: Measuring B -> rho pi decays and the unitarity ang…
The role of the decay mode B->rho pi for the determination of the unitarity angle alpha is critically examined in view of the smaller than expected ratio B(B->rho+/- pi-/+)/B(B->rho0 pi+/-) found by the CLEO collaboration.
We present recent measurements of the unitarity triangle angle phi2(alpha) using B -> pi pi, B -> rho rho, and B -> rho pi decays. The measurements are based on data samples collected with the Belle and BaBar detectors at the KEKB and…
We present results from an analysis of B0->rho+rho- using 316fb^-1 of Y(4S) -> B0B0bar decays observed with the BaBar detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure the B0->rho+rho- branching fraction, longitudinal…
We present improved measurements of the branching fractions and CP-asymmetries in the B0 --> pi+ pi-, B0 --> pi0 pi0, and B+ --> rho+ rho0 decays, which impact the determination of alpha. We find S(pi+ pi-) = -0.68 +/- 0.10 +/- 0.03 C(pi+…
B meson decays involving b -> u transitions are sensitive to the unitarity triangle angle alpha (or phi2). The BaBar and Belle experiments have studied B-meson decays to pipi, rhopi and rhorho final states. It is possible to combine these…
The BABAR collaboration measurements of the B -> pipi, B -> rhopi and B -> rhorho decays are presented. New results, from a 113 fb-1 data sample, on the time-dependent CP asymmetries of the longitudinally polarized component of the B0 ->…
We present results from an analysis of B0 to rho+rho- decays using 383.6 million BB-bar pairs collected by the BaBar detector at the PEP-II asymmetric-energy B Factory at SLAC. The measurements of the B0 to rho+rho- branching fraction,…
The measurements of the angle alpha (phi2) of the unitarity triangle at the B factories are reviewed. The value of alpha determined by combining the results obtained in the B to pi pi, B to rho pi, and B to rho rho modes by both the BABAR…
We determine the domains of the values of unitarity triangle angle alpha, allowed by the charmless strangeless B_d (\bar B_d) decays.
We present results from an analysis of B0 -> rho+rho- using 232 million Upsilon(4S) decays collected with the BABAR detector at the PEP-II asymmetric-energy $B$ Factory at SLAC. We measure the longitudinal polarization fraction f_L = 0.978…
First observations of the B_s0->D_s*- pi+, B_s0->D_s- rho+ and B_s0->D_s*- rho+ decays are reported together with measurements of their branching fractions: B(B_s0->D_s*- pi+)=(2.4 +0.5-0.4(stat.) +-0.3(syst.) +-0.4(fs))x10^(-3), B(Bs->D_s-…
The potential of constraints on the angle alpha of the Unitarity Triangle from studies of B0 -> pi+ pi- pi0 decays is reviewed. The experimental inputs needed for an isospin analysis are starting to become available. The precision of…
We reconsider two classical proposals for the determination of the angle gamma of the unitarity triangle: B^\pm => chi_{c0} \pi^\pm => \pi^+\pi^-\pi^\pm and B_s => rho^0 K_S => \pi^+ \pi^- K_S. We point out the relevance, in both cases, of…
Theoretical errors in the extraction of alpha from B -> pi^+ pi^-, rho^+ rho^-, rho pi decays are usually given in terms of upper bounds on alpha_eff-alpha obtained from isospin or from SU(3) relations, where alpha_eff is measured through…
We measure the branching fraction, polarization and CP asymmetry of B+ -> rho+rho0 decays and search for the decay B+ -> rho+f_0(980) based on a data sample of 231.8 million Y(4S)->BB decays collected with the BaBar detector at the SLAC…
We report on the observation of B-> D(*) pi+ pi- pi- pi^o decays. The branching ratios for D*+ and D*o are (1.72+/-0.14+/-0.24)% and (1.80+/-0.24+/-0.27)%, respectively. Each final state has a D* omega pi- component, with branching ratios…
In the neutral B meson system, it is possible to measure the CKM angle alpha using the decay mode b -> u ubar d in the presence of pollution from gluonic b -> d penguin decays. Here the recent status of the measurements of CP-violating…
Constraints on the CKM angle \gamma are presented from GLW, ADS, and GGSZ analyses of B+- -> D K+- at the LHCb experiment. The branching fractions of B0 -> D0bar K+ \pi- and Bs -> D0bar K- \pi+ are also reported, measured relative to the…
We study B0->rho0rho0 decays in a sample of 465*10^6 Upsilon (4S)->BBbar events collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collider located at the Stanford Linear Accelerator Center (SLAC). We measure the…
The result of a search for the decay Bc+ -> Bs0 pi+ is presented, using the Bs0 -> Ds- pi+ and Bs0 -> J/psi Phi channels. The analysis is based on a data sample of pp collisions collected with the LHCb detector, corresponding to an…