New Results in Radiative Electroweak Penguin Decays at Babar
K. T. Flood · Proceedings of 35th International Conference of High Energy Physics — PoS(ICHEP 2010) · 2011
We report the result of a search for the rare decay B 0 → γγ using 426 fb -1 of data, corresponding to 226 million B 0 B 0 pairs, collected on the ϒ (4S) resonance at the PEP-II asymmetric-energy e + ecollider using the BABAR detector.We use a maximum likelihood fit to extract the signal yield and observe 21 +13 -12 signal events with a statistical signficance of 1.8 σ .This corresponds to a branching fraction B(B 0 → γγ) = (1.7 ± 1.1(stat.)± 0.2(syst.))× 10 -7 .Based on this result, we set a 90% confidence level upper limit of B(B 0 → γγ) < 3.2 × 10 -7 .Using the same dataset, we also set the first upper limit on the rate of the radiative electroweak penguin decay B + → K + τ + τ -.