Isotopes which undergo this decay and thereby emit positrons include, but are not limited to: carbon-11, nitrogen-13, oxygen-15, fluorine-18, copper-64, gallium-68, bromine-78, rubidium-82, yttrium-86, zirconium-89, sodium-22, aluminium-26, potassium-40, strontium-83, and iodine-124. As an example, the following equation describes the beta plus decay of carbon-11 to boron-11, emitting a positron and a neutrino: