Implement higher-order electroweak corrections in νpropa

Implement next-to-leading-order electroweak corrections, or suitable analytic approximations to those corrections, for the inclusive and differential neutrino-interaction cross sections in the νpropa simulation framework.

Background

The νpropa plug-in currently models the relevant neutrino–neutrino, neutrino–antineutrino, and neutrino–photon interactions at leading order and uses on-shell approximations for selected massive-boson production channels. The paper evaluates next-to-leading-order electroweak corrections for representative neutrino-scattering processes and finds that they become substantial at ultra-high centre-of-mass energies, reaching approximately −50%, largely because of Sudakov logarithms.

Direct numerical evaluation of the NLO virtual corrections is too computationally expensive for sampling differential cross sections throughout the full propagation simulation. The unresolved implementation problem is therefore to incorporate these corrections into νpropa, either by pre-tabulating inclusive or differential predictions or by using analytic approximations that capture the dominant high-energy effects.

References

These results indicate that the NLO EW corrections become significant at extremely large centre of mass energies (reaching $-50\%$). We note that the numerical evaluation of the NLO virtual corrections is rather time consuming, and therefore directly evaluating the squared amplitude when sampling the differential cross-section for the various interaction channels does not seem tractable for the full propagation framework. Possible future strategies could be to pre-tabulate the NLO predictions for the inclusive and/or differential cross section. Alternatively, as the dominant numerical contribution of these correction arises from large Sudakov logarithms, it may also be feasible to include analytic approximations for the various interaction channels (at both the differential and inclusive levels)---see, for example, Ref.. The inclusion of these effects as part of the plug-in is left for future work.

— Cascades from ultra-high-energy neutrinos  (2608.30562 - Marco et al., 31 Aug 2026) in Section 3, paragraph “A comment on trident production and radiative corrections”; reiterated in Section 6, Conclusion and prospects