Decays of B mesons to two light pseudoscalars

Anomalies in Hadronic B Decays

In this Letter, we perform fits to B→PP decays, where B={B^{0},B^{+},B_{s}^{0}} and the pseudoscalar P={π,K}, under the assumption of flavor SU(3) symmetry [SU(3)_{F}]. Although the fits to ΔS=0 or ΔS=1 decays individually are good, the combined fit is very poor: there is a 3.6σ disagreement with the SU(3)_{F} limit of the standard model (SM_{SU(3)_{F}}). One can remove this discrepancy by adding SU(3)_{F}-breaking effects, but 1000% SU(3)_{F} breaking is required. The above results are rigorous, group theoretically-no dynamical assumptions have been made. When one adds an assumption motivated by QCD factorization, the discrepancy with the SM_{SU(3)_{F}} grows to 4.4σ.

Determination of weak amplitudes using Bose symmetry and Dalitz plots

We present a new method using Dalitz plots and Bose symmetry of pions that allows the complete determination of the magnitudes and phases of weak decay amplitudes. We apply the method to processes such as B→K*π, with the subsequent decay of K*→Kπ. Our approach enables the additional measurement of an isospin amplitude without any theoretical assumption. This advance will help in measuring the weak phase and probing for new physics beyond the standard model with fewer assumptions.

Obtaining the apex of the unitarity triangle from B-->piK decays

We present a method of obtaining the apex of the unitarity triangle from measurements of B-->piK decay rates alone. Electroweak penguin amplitudes are included, and are related to tree operators. Discrete ambiguities are removed by comparing solutions with independent experimental data. The theoretical uncertainty in this method is about 10%.

Observation of a significant excess of pi0pi0 events in B meson decays

We present a study of the decay B0-->pi(0)pi(0) based on a sample of 124 x 10(6) BB pairs recorded by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We observe 46+/-13+/-3 events, where the first error is statistical and the second is systematic, corresponding to a significance of 4.2 standard deviations including systematic uncertainties. We measure the branching fraction B(B0-->pi(0)pi(0))=(2.1+/-0.6+/-0.3)x10(-6), averaged over B0 and B(0) decays.

Possibility of large final state interaction phases in light of B --> kpi and pipi data

The newly observed &Bmacr;( 0)-->&Kmacr;( 0)pi(0) mode is quite sizable while pi(-)pi(+) is rather small. Data also hint at pi(-)pi(0) greater, similarpi(-)pi(+). Though consistent with zero, central values of CP violating asymmetries in K-pi(+,0) and &Kmacr;( 0)pi(-) show an interesting pattern. Taking cue from these, we suggest that, besides gamma identical witharg(V(*)(ub)) being large, the rescattering phase delta in Kpi and pipi modes may be greater than 90 degrees. If this is true, not only the above trends can be accounted for, but one would also find pi(0)pi(0) approximately pi(-)pi(+,0), and the CP asymmetry in &Bmacr;( 0) vs B0-->pi(-)pi(+) could be as large as -60%. These results can be tested in a couple of years.