We report measurements of isospin asymmetry Delta(0-) and difference of direct CP asymmetries Delta A(CP) between charged and neutral B -> X-s gamma decays. This analysis is based on the data sample containing 772 x 10(6)B (B) over bar pairs that was collected with the Belle detector at the KEKB energy-asymmetric ethornecollider. Using a sum-of-exclusive technique with invariant X-s mass up to 2.8 GeV= c2, we obtain Delta(0-) = [0.48 +/- 1.49(stat) +/- 0.97(syst) +/- 1.15(f(+-)/f(00))]% and Delta A(CP) = [+3.69 +/- 2.65(stat) +/- 0.76(syst)]%, where the last uncertainty for.0-is due to the uncertainty on the production ratio of B+B- to B-0(B) over bar (0) in.o4Sthorn decays. The measured value of Delta(0-) is consistent with zero, allowing us to constrain the resolved photon contribution in the B -> X-s gamma, and improve the branching fraction prediction. The result for Delta A(CP) is consistent with the prediction of the SM. We also measure the direct CP asymmetries for charged and neutral B -> X-s gamma decays. All the measurements are the most precise to date.
Matthias Finger, Konstantin Androsov, Qian Wang, Jan Steggemann, Yiming Li, Anna Mascellani, Varun Sharma, Xin Chen, Rakesh Chawla, Matteo Galli
Matthias Finger, Konstantin Androsov, Jan Steggemann, Qian Wang, Anna Mascellani, Yiming Li, Varun Sharma, Xin Chen, Rakesh Chawla, Matteo Galli