2020/05/12 by Hai-Yang Cheng, Cheng, Hai-Yang
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2005.06080
openalex publication_date 2020/05/12 · openalex created_date 2024/04/10 · openalex updated_date 2026/07/28
The decay amplitude of B+→ π+π-π+ in the Dalitz plot has been analyzed by the LHCb using three different approaches for the S-wave component. It was found that the mode with σ (or f0(500)) exhibited a CP asymmetry of 15% in the isobar model, whereas the f2(1270) mode had a 40% asymmetry. On the contrary, CP asymmetry for the dominant quasi-two-body decay B-→ρ0π- was found to be consistent with zero in all three approaches, while all the existing theoretical predictions lead to a negative CP asymmetry ranging from -7% to -45%. We show that the nearly vanishing CP violation in B-→ρ0π- is understandable in the framework of QCD factorization (QCDF). It arises from the 1/mb power corrections to the penguin amplitudes due to penguin annihilations and to the color-suppressed tree amplitude due to hard spectator interactions. Penguin annihilation and hard spectator interactions contribute destructively to ACP(B-→ρ0π-) to render it consistent with zero. The branching fraction and CP asymmetry in B-→σ/f0(500)π- are investigated in QCDF with results in agreement with experiment.