Electron Antineutrino Interaction with Deuterons

The reaction $d({\overline{v}}_e, e^{+})2n$ has been observed using antineutrinos from a powerful fission reactor. The measured cross section ${\overline{\sigma }}_{\mathrm{expt}}=3.0\mathrm{}\pm 1.5\times {10}^{-45\mathrm{}}$ ${\mathrm{cm}}^2$/fission ${\overline{v}}_e$ is consistent with expectations, ${\overline{\sigma }}_{\mathrm{theor}}=2.4\mathrm{}\pm 0.4\times {10}^{-45\mathrm{}}$ ${\mathrm{cm}}^2$/fission ${\overline{v}}_e$, based on the two-component neutrino theory and elementary considerations regarding the structure of the deuteron.