Nuclear reaction 1: ²³⁸U + n⁰ → ²³⁹U.
Nuclear reaction 2: ²³⁹U → ²³⁹Np + e⁻ + electron antineutrino.
Nuclear reaction 3: ²³⁹Np → ²³⁹Pu + e⁻ + electron antineutrino.
Beta decay is radioactive decay in which a beta ray and a neutrino are emitted from an atomic nucleus.
There are two types of beta decay: beta minus and beta plus. In beta minus decay, neutron is converted to a proton and an electron and an electron antineutrino.