Beta rays

A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus, known as beta decay. There are two forms of beta decay, β− decay and β+ decay, which produce electrons and positrons, respectively. Beta particles with an energy of 0.5 MeV have a range of about one metre in the air, and can't pass through clothing or thin metal sheets; the distance is dependent on the particle's energy and the air's density and composition. Beta particles are a type of ionizing radiation, and for radiation protection purposes, they are regarded as being more ionizing than gamma rays, but less ionizing than alpha particles. The higher the ionising effect, the greater the damage to living tissue, but also the lower the penetrating power of the radiation through matter. The ionising effect of a beta particle is caused by the particle knocking electrons from shells by either the electrostatic force or energy transfer from the beta particle to the electron by collision. They produce roughly 100 ion pairs per cm in air, this means an ion plus a released electron.