Revisiting the B 0 → π 0 π 0 decays in the perturbative QCD approach
Abstract
We recalculate the branching ratio and CP asymmetry for
B
¯
0
(
B
0
)→
π
0
π
0
decays in the Perturbative QCD approach. In this approach, we consider all the possible diagrams including non-factorizable contributions and annihilation contributions. We obtain
Br(
B
¯
0
(
B
0
)→
π
0
π
0
)=(
1.17
+0.11
−0.12
)×
10
−6
. Our result is in agreement with the latest measured branching ratio of
B
0
→
π
0
π
0
by the Belle and HFAG Collaborations. We also predict large direct CP asymmetry and mixing CP asymmetry in
B
0
→
π
0
π
0
decays, which can be tested by the coming Belle-II experiments.