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arXiv · 2304.05784

Accessing the gluon GTMD $\boldsymbol{F_{1,4}}$ in exclusive $\boldsymbol{\pi^0}$ production in $\boldsymbol{ep}$ collisions

Shohini Bhattacharya·Duxin Zheng·Jian Zhou
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Abstract

We demonstrate that the longitudinal single target-spin asymmetry in exclusive $\pi^0$ production in $ep$ collisions can give access to the imaginary part of the gluon generalized transverse momentum distribution (GTMD) $F_{1,4}$. Such a longitudinal spin asymmetry that results from the Coulomb-nuclear interference effect, leads to a characteristic azimuthal angular correlation of $\sin 2\phi$, where $\phi$ is the azimuthal angle between the scattered lepton transverse momentum and the recoiled proton's transverse momentum. We also present a numerical estimate of the asymmetry for the kinematics accessible at EIC and EicC.

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Shohini Bhattacharya, Duxin Zheng, Jian Zhou. 2023-04-12. Accessing the gluon GTMD $\boldsymbol{F_{1,4}}$ in exclusive $\boldsymbol{\pi^0}$ production in $\boldsymbol{ep}$ collisions. https://arxiv.org/abs/2304.05784

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