Possible implications of a reactor-status effect on the β+ decay rate of 22Na

Recently, a reproducible reactor-status effect was measured for the decay of 22Na. However, the effect was not observable for the β- decay of 60Co. Since no systematic cause for this effect was found, the possibility exists that it is caused by an interaction of reactor antineutrinos with the source nucleus. The observed effect is 18 orders of magnitude larger than for the antineutrino capture of a free proton. A possible explanation is a final-state interaction between the incoming antineutrino and a neutrino in the source nucleus. The effect has still to be confirmed by an independent measurement. In this paper, the consequences for applications in monitoring nuclear facilities are discussed, as well as the consequences for fundamental physics and the opportunities for resolving some outstanding questions about neutrino properties.