Beta decay is very complex phenomena in natural radioactive decay. There are 3 types of Beta decay.
B+ decay (Beta plus or Beta positive or positron decay):
is the conversion of a proton into a neutron plus a positron and an electron neutrino.
B- decay (Beta negative or Beta nought):
is the conversion of a neutron into a proton plus an electron and a electron antineutrino.
Note: a positron is the a positive electron or the antiparticle of the electron.
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