[论文解读] Real radiative decays of heavy pseudoscalar mesons

Teseo San Jose, Yasumichi Aoki+10 more|arXiv (Cornell University)|Mar 20, 2026

Quantum Chromodynamics and Particle Interactions被引用 0

一句话总结

论文概述了对重 pseudoscalar 像素子   的辐射肽解耦泄耦过程 P  ν  的晶格 QCD 研究，重点提取 hadronic form factors F_V 和 F_A，并概述朝向完整 QCD+QED 计算的方法。

ABSTRACT

We report our ongoing lattice QCD study of radiative leptonic decays of the charged pseudoscalar mesons $D$, $D_s$, $B$, and $B_c o \ell ν_\ell γ$. We carry out our analysis on a single JLQCD ensemble with lattice spacing $a=0.044~ ext{fm}$. This work is a step towards a complete QCD+QED lattice calculation of these modes, aimed at reducing theoretical uncertainties in the extraction of $|V_{cd}|$ and $|V_{cs}|$ and providing first-principles estimates of the corresponding form factors in the $B$ sector.

研究动机与目标

• Motivate the study of real radiative decays P      to reduce theory uncertainties in |V_cd| and |V_cs| and to provide first-principles form factors for B mesons.
• Develop and apply a lattice QCD method to compute the hadronic tensor components governing P    decays.
• Assess systematic effects and establish groundwork for including quark-disconnected diagrams and QED corrections in future work.

提出的方法

• Represent the hadronic tensor H^{μν}_{V-A} via time-ordered correlators of the electromagnetic and weak currents.
• Decompose H^{μν}_{V-A} into F_V and F_A for on-shell photons, noting H_1 and H_2 do not contribute in this kinematic limit.
• Compute Euclidean three-point functions C^{μν}_{3,V-A} with photon insertion and project onto photon energy to extract F_V and F_A.
• Use twisted boundary conditions and Fourier modes to access a dense set of x_γ values and photon momenta.
• Employ Möbius domain-wall fermions on a JLQCD ensemble with specified lattice spacing to study D, D_s, B, and B_c-like heavy masses.

(a)

实验结果

研究问题

• RQ1 What are the lattice-determined values of the radiative form factors F_V and F_A for real photons in heavy pseudoscalar decays?
• RQ2 How can lattice QCD with QCD+QED groundwork reduce uncertainties in |V_cd| and |V_cs| and inform B-meson radiative form factors?
• RQ3 What is the impact of including quark-disconnected diagrams and different lattice spacings/ masses on the extracted form factors?

主要发现

• Initial lattice data for the three-point function C^{μν}_{3,V-A} show measurable vector and axial components for D and D_s with a given photon direction and momentum.
• The method enables access to multiple photon energies E_γ via Fourier modes and twist angles, increasing x_γ coverage.
• A plan to include quark-disconnected contributions and to perform multi-lattice, multi-mass studies is outlined for future work.

(b)