# NLO electroweak radiative corrections for four-fermionic process at Belle II

## TL;DR

This paper calculates next-to-leading order electroweak radiative corrections for the e+e- to fermion pair process at Belle II, highlighting their significance and kinematic dependence for precise measurements.

## Contribution

It provides detailed NLO electroweak correction calculations for the four-fermion process at Belle II, including polarization effects and arbitrary energy cuts, which were not previously available.

## Key findings

- Radiative corrections are significant and kinematically dependent.
- Hard bremsstrahlung effects are included for various energy cuts.
- Results are crucial for ultra-precise measurements at Belle II.

## Abstract

We discuss the next to the leading order (NLO) electroweak radiative corrections to the $e^- e^+ \rightarrow f^- f^+ (\gamma)$ cross section asymmetry, for polarized and unpolarized beam scenario. The left-right and forward-backward amplitudes, with and without radiative corrections, are evaluated and compared for various kinematics. The hard bremsstrahlung is included for arbitrary energy cuts. The radiative corrections are shown to be significant and having a non-trivial dependency on the kinematic conditions. The calculations are relevant for the ultra-precise low-energy experiment Belle~II planned at SuperKEKB.