Revisiting and decays using the modified perturbative QCD approach

Ru-Xuan Wang; Mao-Zhi Yang

doi:10.1140/epjc/s10052-025-13840-8

EPJ

a
b
c
d
e
ap
st
h
plus
ds
pv
ti
qt
am
n

2023 Impact factor 4.2

Particles and Fields

Open Access

Eur. Phys. J. C (2025) 85: 146
https://doi.org/10.1140/epjc/s10052-025-13840-8

Regular Article - Theoretical Physics

Revisiting $B \to K^{} π$ $B\rightarrow K^\pi$ and $B \to K ρ$ $B\rightarrow K\rho$ decays using the modified perturbative QCD approach

Ru-Xuan Wang^a and Mao-Zhi Yang^b

School of Physics, Nankai University, 300071, Tianjin, People’s Republic of China

^a wangrx@mail.nankai.edu.cn
^b yangmz@nankai.edu.cn

Received: 16 November 2024
Accepted: 20 January 2025
Published online: 5 February 2025

Abstract

We revisit $B \to K^{*} π$ $B\rightarrow K^*\pi$ and $B \to K ρ$ $B\rightarrow K\rho$ decay processes using the modified perturbative QCD approach, which is developed based on the perturbative QCD approach with a few improvements. A critical infrared cutoff scale $μ_{c}$ $\mu _c$ is introduced to separate hard and soft contributions in the decay process. Hard contributions with scale $μ$ $\mu$ larger than $μ_{c}$ $\mu _c$ are calculated with perturbative QCD, and soft contributions with $μ < μ_{c}$ $\mu <\mu _c$ are described in terms of soft transition and production form factors. In addition, color-octet contributions are considered phenomenologically. The branching fractions and CP violations of $B \to K^{*} π$ $B\rightarrow K^*\pi$ , $K ρ$ $K\rho$ decays are calculated. With appropriate parameter inputs, the theoretical results can be in good agreement with experimental data.

© The Author(s) 2025

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.