研究 Belle II B 介子的三體衰變

本論文主要在研究 B^± → K^± π^± π^∓ 的分支分數和電荷宇稱破壞在 Belle II 實驗結果。我們分析了在在 Υ(4S) 共振態下積分亮度共 62.8 反飛靶的正負電子對撞數據。得到分支分數為 B (B^± → K^± π^± π^∓ ) = [5.80 ± 0.29(stat) ± 0.97(sys)] × 10^−5，宇稱破壞的測量結果為 A cp (B^± → K^± π^± π^∓ ) = −0.017 ± 0.049(stat) ± 0.019(sys)。由於 B^± → K^± π^± π^∓ 有許多共振態，每一個共振態的測量效率不一致且會有干涉效應，這次的測量結果與世界的平均值接近。

關鍵字

Belle II 實驗； B 衰變

並列摘要

We are studying the branching fraction and A cp of the decay mode B^± → K^± π^± π^∓ in Belle II experiment. We analyze the data at the Υ(4S) resonance, corresponding to 62.8 fb−1 of integrated luminosity. In this study, we use two dimensional M bc × ∆E fitting to determine the signal yields. We obtain the branching fractions B (B^± → K^± π^± π^∓ ) = B (B^± → K^± π^± π^∓ ) = [5.80±0.29(stat)±0.97(sys)]×10^−5 and the direct CP asymmetry is A cp (B^± → K^± π^± π^∓ ) = A cp (B^± → K^± π^± π^∓ ) = −0.017 ± 0.049(stat) ± 0.019(sys). Since there are a lot of resonance states in B^± → K^± π^± π^∓ , and each state has different efficiency and interference, the results are similar to world average.

並列關鍵字

Belle II ； B decay

參考文獻

[1] I. H. de la Cruz, The Belle II experiment: fundamental physics at the flavor frontier, Journal of Physics Conference Series (2016).

Google Scholar

[2] P. Zyla et al. , Particle Data Group, Review of Particle Physics, to be published in Prog. Theor. Exp. Phys. 2020, https://pdg.lbl.gov/2020/html/authors_2020.html, LHCb Public Notes 2020.