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arXiv · 2401.12162

Threshold photoproduction of $\eta_c$ and $\eta_b$ using holographic QCD

Florian Hechenberger·Kiminad A. Mamo·Ismail Zahed
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Abstract

We discuss the possibility that threshold photoproduction of $\eta_{c,b}$ may be sensitive to the pseudovector $1^{+-}$ glueball exchange. We use the holographic construction to identify the pseudovector glueball with the Kalb-Ramond field, minimally coupled to bulk Dirac fermions. We derive the holographic C-odd form factor and its respective charge radius. Using the pertinent Witten diagrams, we derive and analyze the differential photoproduction cross section for $\eta_{c,b}$ in the threshold regime, including the interference from the dual bulk photon exchange with manifest vector dominance. The possibility of measuring this process at current and future electron facilities is discussed.

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Florian Hechenberger, Kiminad A. Mamo, Ismail Zahed. 2024-01-22. Threshold photoproduction of $\eta_c$ and $\eta_b$ using holographic QCD. https://doi.org/10.1103/physrevd.109.074013

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