Joint explanation of the B→πK puzzle and the B→Kνν¯ excess

IF 5 2区物理与天体物理 Q1 Physics and Astronomy

Physical Review D Pub Date : 2025-04-29 DOI:10.1103/physrevd.111.075029

W. Altmannshofer, S. Roy

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引用次数: 0

Abstract

In light of the recent branching fraction measurement of the B+→K+νν¯ decay by Belle II and its poor agreement with the Standard Model expectation, we analyze the effects of an axionlike particle (ALP) in B meson decays. We assume a long-lived ALP with a mass of the order of the pion mass that decays to two photons. We focus on a scenario where the ALP decay length is of the order of meters such that the ALP has a non-negligible probability to decay outside the detector volume of Belle II, mimicking the B+→K+νν¯ signal. Remarkably, such an arrangement is also relevant for the long-standing B→πK puzzle by noting that the measured B0→π0K0 and B+→π0K+ decays could have a B0→aK0 and B+→aK+ component, respectively. We also argue based on our results that the required ALP-photon effective coupling belongs to a region of parameter space that can be extensively probed in future beam dump experiments like SHiP.

Published by the American Physical Society

2025

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B→πK谜题和B→k ν¯过量的联合解释

鉴于Belle II最近对B+→K+νν¯衰变的分支分数测量及其与标准模型预期的不一致，我们分析了类轴子粒子（ALP）在B介子衰变中的作用。我们假设有一个寿命很长的ALP，它的质量与介子的质量相当，衰变为两个光子。我们关注的场景是ALP衰减长度为米数量级，使得ALP在Belle II的探测器体积之外有不可忽略的衰减概率，模拟B+→K+ν¯信号。值得注意的是，这种排列也与长期存在的B→πK之谜有关，因为测量到的B0→π0K0和B+→π0K+衰变可能分别具有B0→aK0和B+→aK+成分。我们还根据我们的结果认为，所需的alp -光子有效耦合属于一个参数空间区域，可以在未来的光束转储实验中广泛探索，如SHiP。2025年由美国物理学会出版

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来源期刊

Physical Review D 物理-天文与天体物理

CiteScore

9.20

自引率

36.00%

发文量

审稿时长

2 months

期刊介绍： Physical Review D (PRD) is a leading journal in elementary particle physics, field theory, gravitation, and cosmology and is one of the top-cited journals in high-energy physics. PRD covers experimental and theoretical results in all aspects of particle physics, field theory, gravitation and cosmology, including: Particle physics experiments, Electroweak interactions, Strong interactions, Lattice field theories, lattice QCD, Beyond the standard model physics, Phenomenological aspects of field theory, general methods, Gravity, cosmology, cosmic rays, Astrophysics and astroparticle physics, General relativity, Formal aspects of field theory, field theory in curved space, String theory, quantum gravity, gauge/gravity duality.