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arXiv · 2603.19960

Real radiative decays of heavy pseudoscalar mesons

Teseo San Jose·Yasumichi Aoki·Matteo Di Carlo·Felix Erben·Vera Gülpers·Maxwell T. Hansen·Shoji Hashimoto·Nils Hermansson-Truedsson·Ryan Hill·Takashi Kaneko·Antonin Portelli·Justus Tobias Tsang
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Abstract

We report our ongoing lattice QCD study of radiative leptonic decays of the charged pseudoscalar mesons $D$, $D_s$, $B$, and $B_c \to \ell \nu_\ell \gamma$. We carry out our analysis on a single JLQCD ensemble with lattice spacing $a=0.044~\text{fm}$. 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.

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Teseo San Jose, Yasumichi Aoki, Matteo Di Carlo, Felix Erben, Vera Gülpers, Maxwell T. Hansen, Shoji Hashimoto, Nils Hermansson-Truedsson, Ryan Hill, Takashi Kaneko, Antonin Portelli, Justus Tobias Tsang. 2026-03-20. Real radiative decays of heavy pseudoscalar mesons. https://arxiv.org/abs/2603.19960

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