Question

What is beta minus?

Answer 1

A `beta^-` particle is just an electron, `""_(-1)^(0) e`. We see that in `bb(beta^-)` decay, or we sometimes call it "beta decay". In this process, a neutron will split into a proton and electron as given below:

`""_(1)^(0) n -> ""_(1)^(1)p + ""_(-1)^(0)e`, `" "Z -> Z + 1`

(here we ignore neutrinos and antineutrinos.)

In fact, it is the only nuclear decay process out of `alpha` decay, `beta` decay, positron emission, and electron capture to raise the atomic number by `1`.

One might also call it the reverse process to electron capture, wherein a core electron is assimilated by a proton in the nucleus to form a neutron.

`""_(1)^(1) p + ""_(-1)^(0) e -> ""_(1)^(0) n`, `" "Z -> Z - 1`

(again, here we ignore neutrinos and antineutrinos.)