Xin Guan

collaborators

3 papers

hep-ph2025

Two-loop QCD-corrections to $e^{+} e^{-} \to Z^{*} \to J / ψ + J / ψ$

Xiang Chen, Xin Guan, Chuan-Qi He +1

We present a next-to-next-to-leading-order calculation within the nonrelativistic QCD framework for the process of $e^{+} e^{-} \to Z^{*} \to J / ψ + J / ψ$ . We find t…

hep-ph2025

Analytical two-loop amplitudes of $e^{+} e^{-} ⟶ J / ψ + η_{c}$ at $B$ factories

Xiang Chen, Xin Guan, Chuan-Qi He +3

In double charmonium production, a long-standing challenge is that the theoretical predictions are not consistent with the measurements at B factories. Within the NRQCD framework,…

hep-ph2024

Determination of the Strong Coupling Constant $α_{s}$ from Inclusive Semi-leptonic $B$ Meson Decays

Yuzhi Che, Long Chen, Jinfei Wu +5

We demonstrate the feasibility of determining the strong coupling constant, $α_{s}$ , from the inclusive semileptonic decay width of $B$ mesons. We express the semileptonic $B$ decay…

Two-loop QCD-corrections to e+e−→Z∗→J/ψ+J/ψ

Analytical two-loop amplitudes of e+e−⟶J/ψ+ηc​ at B factories

Determination of the Strong Coupling Constant αs​ from Inclusive Semi-leptonic B Meson Decays

Two-loop QCD-corrections to $e^{+} e^{-} \to Z^{*} \to J / ψ + J / ψ$

Analytical two-loop amplitudes of $e^{+} e^{-} ⟶ J / ψ + η_{c}$ at $B$ factories

Determination of the Strong Coupling Constant $α_{s}$ from Inclusive Semi-leptonic $B$ Meson Decays