2025/07/28 by Qiming Feng, Feng, Qi-Ming, Cong‐Feng Qiao +1
Physics and Astronomy · #Particle physics theoretical and experimental studies #High-Energy Particle Collisions Research #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2507.20654
The quarkonium production in association with a heavy-quark pair of the same flavor was found plays an important role in various production schemes, let alone it provides a distinctive signature that could be studied in experiment. Within the NRQCD framework, we perform the first complete calculation of the hadroproduction process gg→ J/ψ+cc at the next-to-leading order (NLO) in the expansion of strong coupling constant αs. The result tells that the NLO corrections substantially enhance the color-singlet yield and alter the predicted polarization patterns, and hence lead to a better agreement with experimental data across the pT spectrum. In contrast to charm-quark fragmentation, the J/ψ and cc associated production channel displays a markedly different kinematic behavior, underscoring its distinct role in the production mechanism. While the inclusion of this process greatly reduces the discrepancy between color-singlet theoretical prediction and experimental measurement, a residual gap of approximately one order of magnitude still remains.