We report the result of a search for the rare decay B0→γγ in 426fb-1 of data, corresponding to 226×106 B0B ̄0 pairs, collected on the Υ(4S) resonance at the PEP-II asymmetric-energy e+e- collider using the BABAR detector. We use a maximum likelihood fit to extract the signal yield and observe 21-12+13 signal events with a statistical significance of 1.8σ. This corresponds to a branching fraction B(B0→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(B0→γγ)<3.2×10 -7.
Sanchez, P., Lees, J., Poireau, V., Prencipe, E., Tisserand, V., Tico, J., et al. (2011). Search for the decay B0→γγ. PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY, 83(3) [10.1103/PhysRevD.83.032006].
Search for the decay B0→γγ
Martinelli M;CARPINELLI, MassimoMembro del Collaboration Group
;
2011
Abstract
We report the result of a search for the rare decay B0→γγ in 426fb-1 of data, corresponding to 226×106 B0B ̄0 pairs, collected on the Υ(4S) resonance at the PEP-II asymmetric-energy e+e- collider using the BABAR detector. We use a maximum likelihood fit to extract the signal yield and observe 21-12+13 signal events with a statistical significance of 1.8σ. This corresponds to a branching fraction B(B0→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(B0→γγ)<3.2×10 -7.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.