We used data mainly collected by OPAL experiment to test the signal significance of a parameter ε, which is equal to zero in SM. For total cross sections, we obtained no derivation of enough significance. But for differential cross sections, some derivation over 3σ are observed(statistical uncertainty only), indicating that this contact interaction might exist.
@article{arxiv.2411.15686,
title = {New test on contact interactions in the data at $\sqrt{s}$ 130-207GeV by Bhabha scattering process $e^+e^-\to e^+e^-$},
author = {Zhikun Xi and Minghui Liu and Jürgen Ulbricht},
journal= {arXiv preprint arXiv:2411.15686},
year = {2024}
}