Quasi-two-body decays B→Pf0(500)→Pπ+π− in the perturbative QCD approach

Abstract

In this paper, we study the quasi-two-body decays B→Pf0(500)→Pπ+π− [with P=(π,K,η,η′)] within framework of perturbative QCD (PQCD) factorization approach. With the help of π−π distribution amplitude and scalar form factor Fππ(ω2), we calculate the CP averaged branching fraction and the CP asymmetry for the quasi-two-body decays B→Pf0(500)→Pπ+π−. Taking the quasi-two-body decay B+→π+f0(500)→π+π+π− as an explicit example, we present the behavior of differential branching fraction and direct CP violation versus the π−π invariant mass. The total branching fraction and direct CP violation are B(B+→π+[σ→]π+π−)=(1.78±0.41±0.51)×10−6 and ACP(B+→π+[σ→]π+π−)=(29.8±11.1±13.0)% respectively. Our results could be tested by further experiments. Published by the American Physical Society 2024