https://doi.org/10.1140/epjc/s10052-019-6544-7
Regular Article - Theoretical Physics
Quasi-two-body decays 
in perturbative QCD approach
1
Department of Physics, College of Sciences, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, People’s Republic of China
2
Institute of Theoretical Physics, Shanxi University, Taiyuan, 030006, Shanxi, People’s Republic of China
3
Department of Mathematics and Physics, Nanjing Institute of Technology, Nanjing, 211167, Jiangsu, People’s Republic of China
4
Department of Physics and Institute of Theoretical Physics, Nanjing Normal University, Nanjing, 210023, Jiangsu, People’s Republic of China
* e-mail: liyakelly@163.com
Received:
27
September
2018
Accepted:
27
December
2018
Published online:
17
January
2019
We extend our recent works on the P-wave two-pion resonant contributions to the kaon-pion cases in the hadronic charmless B meson decays by employing the perturbative QCD approach. The concerned decay modes are analysed in the quasi-two-body framework by parameterizing the kaon-pion distribution amplitude 
, which contains the final state interactions between the kaon and pion in the resonant region. The relativistic Breit–Wigner formula for the P-wave resonant state 
is adopted to parameterize the time-like form factor 
. We calculate the CP-averaged branching ratios and direct CP-violating asymmetries of the quasi-two-body decays 
, with 
, in this work. It is shown that the agreement of theoretical results with the experimental data can be achieved, through which Gegenbauer moments of the P-wave kaon-pion distribution amplitudes are determined. The predictions in this work will be tested by the precise data from the LHCb and the future Belle II experiments.
© The Author(s), 2019
