https://doi.org/10.1140/epjc/s10052-019-7484-y
Regular Article - Theoretical Physics
Calculation of the 
decays in the perturbative QCD approach
1
Department of Physics, Yantai University, Yantai, 264005, China
2
Center for High Energy Physics, Peking University, Beijing, 100871, China
3
Department of Physics, Jiangsu Normal University, Xuzhou, 221116, China
* e-mail: liying@ytu.edu.cn
Received:
29
October
2019
Accepted:
11
November
2019
Published online:
22
November
2019
Motivated by the observations of the decays 
and 
from BaBar collaboration, we study the 
decays in the perturbative QCD approach for the first time. In the absence of reliable nonperturbative wave functions we only assume the scalar meson 
and 
are two-quark ground states. In our calculations, these decays are all dominated by the hard-scattering emission and annihilation diagrams, while the factorizable emission diagrams are forbidden or suppressed heavily by the vector decay constants. Furthermore, the branching fractions are sensitive to the mixing between and . Comparing our results with the experimental data, a large mixing angle 
is favored. Taking 
, the orders of branching fractions of 
, 
and 
are predicted to be 
, 
and 
, respectively, which can be measured in the current experiments such as LHCb and Belle-2. In addition, although these decays are penguin dominant, the mixing also leads to large direct CP asymmetries in these decays. With the precise data in future, our results could shed light on the inner structure of the scalar mesons and can be used to determine the mixing angle of the 
system.
© The Author(s), 2019
