Next-to-leading order QCD corrections to $B_c^*\to J/\psi$ form factors

TL;DR

This paper calculates the next-to-leading order QCD corrections to the form factors of the semileptonic decay $B_c^* o J/ar{ ext{psi}}$, providing analytical results and analyzing their behavior across the full momentum transfer range.

Contribution

It presents the first complete analytical NLO QCD correction calculations for $B_c^* o J/ar{ ext{psi}}$ form factors within NRQCD, including asymptotic expressions and scale dependence analysis.

Findings

NLO corrections are significant and convergent at small $q^2$.

NLO corrections reduce renormalization scale dependence.

Full $q^2$ range form factors are provided.

Abstract

Within the framework of Non-Relativistic Quantum Chromodynamics (NRQCD) factorization, we calculate the next-to-leading order (NLO) perturbative QCD corrections to the form factors for the semileptonic decays of $B_c^*$ into $J/\psi$ via (axial-)vector and (axial-)tensor currents. We obtain the complete analytical results for the form factors up to NLO, and provide their asymptotic expressions in the hierarchical heavy quark limit. The NLO corrections are found to be both significant and convergent in the relatively small squared transfer momentum ($q^2$) region, while also reducing the dependence on the renormalization scale $\mu$. Finally, the theoretical predictions for $B_c^*\to J/\psi$ form factors over the full $q^2$ range are provided.