Radiative corrections to inverse beta decay: a precision analysis for reactor neutrinos

Abstract

We present a complete calculation of radiative corrections to the inverse beta decay reaction, ${\overline{\nu }}_e+p\to e^{+}+n$, at reactor antineutrino energies using heavy-baryon chiral perturbation theory. Our analysis consistently incorporates quantum electrodynamics, chromodynamics, and electroweak contributions for the first time within this framework. We provide updated, high-precision cross-section predictions with a full error budget and present the positron energy spectrum, including radiative effects. The results are essential for normalizing the reactor antineutrino flux, determining neutrino oscillation parameters with subpercent accuracy, and searching for new physics at nuclear power plants.

Comments: 7 pages, 4 figures, version published in Physical Review Letters, extended discussions on the relation to the experiment, a change in Fig. 3, minor text edits