A very highly charged gamma ray is given off when the parent isotope falls into a lower energy state. Gamma radiation is the most penetrating of all. These photons can pass through the body and cause damage by ionizing all the molecules in their way. A positron is exactly like an electron in mass and charge force except with a positive charge. It is formed when a proton breaks into a neutron with mass and no charge and this positron with no mass and the positive charge.
Positron emission is most common in lighter elements with a low neutron to proton ratio.
This captured electron joins with a proton in the nucleus to form a neutron. Electron capture is common in larger elements with a low neutron to proton ratio. All elements with an atomic number over 83 are considered radioactive. Radiation ionizes the atoms in the cylinder and allows current to flow between the electrodes. All radioactive elements disintegrate according to their specific half life .