Complete NLO NRQCD calculation of inclusive J/psi plus charm-pair production

Complete the next-to-leading-order QCD calculation within the NRQCD factorization framework for inclusive e+e− → J/ψ + c c̄ production, including both color-singlet and color-octet contributions.

Background

The paper distinguishes inclusive J/ψ production in e+e− annihilation into J/ψ + c c̄ and J/ψ + X_non-c c̄ channels. For the J/ψ + c c̄ channel, the cited literature had calculated only the color-singlet contribution, leaving a complete NLO NRQCD treatment unavailable. This is relevant to determining whether color-octet mechanisms contribute significantly to inclusive charmonium production at the low energies characteristic of B factories.

References

For the former, a complete QCD next-to-leading order (NLO) study within the NRQCD framework is still lacking, as existing calculations have been restricted to the CS contributions.

— Inclusive productions of $J/ψ+η_c$ in $e^{+}e^{-}$ annihilation at Belle  (2609.09590 - Sun et al., 9 Sep 2026) in Section 1, Introduction