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arXiv · 2504.02453

Heavy meson lightcone distribution amplitudes from Lattice QCD

Xue-Ying Han·Jun Hua·Cai-Dian Lü·Andreas Schäfer·Yushan Su·Wei Wang·Ji Xu·Yibo Yang·Jian-Hui Zhang·Qi-An Zhang·Shuai Zhao
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Abstract

Lightcone distribution amplitudes (LCDAs) within the framework of heavy quark effective theory (HQET) play a crucial role in the theoretical description of weak decays of heavy bottom mesons. However, the first-principle determination of HQET LCDAs faces significant theoretical challenges. In this presentation, we introduce a practical approach to address these obstacles. This makes sequential use of effective field theories. Leveraging the newly-generated lattice ensembles, we present a pioneering lattice calculation, offering new insights into LCDAs for heavy mesons. Additionally, we discuss the impact of these results on the heavy-to-light form factors and briefly give potential future directions in this field.

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Xue-Ying Han, Jun Hua, Cai-Dian Lü, Andreas Schäfer, Yushan Su, Wei Wang, Ji Xu, Yibo Yang, Jian-Hui Zhang, Qi-An Zhang, Shuai Zhao. 2025-04-03. Heavy meson lightcone distribution amplitudes from Lattice QCD. https://arxiv.org/abs/2504.02453

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