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arXiv · 2111.14563

Progress in the determination of Mellin moments of the pion LCDA using the HOPE method

William Detmold·Anthony V. Grebe·Issaku Kanamori·C. -J. David Lin·Santanu Mondal·Robert J. Perry·Yong Zhao
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Abstract

The pion light-cone distribution amplitude (LCDA) is a central non-perturbative object of interest for the calculation of high-energy exclusive processes in quantum chromodynamics. In this article, we discuss the calculation of the second and fourth Mellin moment of the pion LCDA using a heavy-quark operator product expansion. The resulting value for the second Mellin moment is $ \langle{ \xi^2 }\rangle(\mu = 2~\text{GeV})= 0.210 \pm 0.013\text{ (stat.)} \pm 0.034\text{ (sys.)}$. This result is compatible with those from previous determinations of this quantity.

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William Detmold, Anthony V. Grebe, Issaku Kanamori, C. -J. David Lin, Santanu Mondal, Robert J. Perry, Yong Zhao. 2021-11-29. Progress in the determination of Mellin moments of the pion LCDA using the HOPE method. https://arxiv.org/abs/2111.14563

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