| The weak nuclear force is involved, and the neutron is converted into a proton when the beta particle is emitted. |
| Next smaller in mass is the beta particle, which is identical in mass and charge to an electron. |
| Beta emissions involve the loss of an electron from the nucleus as a beta particle during the conversion of a neutron into a proton. |
| When a nucleus ejects a beta particle, one of the neutrons in the nucleus is transformed into a proton. |
| Adding a neutron, which has one unit of mass, to 238 U gives 239 U, which decays rapidly to a new element by emitting a beta particle. |
| Its existence was suggested to explain missing energy and angular momentum when a beta particle was emitted from a radioactive element. |
