An unstable (ie, radioactive) nucleus can become more stable after emitting particles and energy. This process is called decay (Radioactive decay). These particles or energy (the latter emitted by electromagnetic waves) are collectively referred to as radiation. The radiation emitted by unstable nuclei can be alpha (helium nucleus) particles, beta (electrons or positrons) particles, gamma rays or neutrons.
During the decay process of a radionuclide, the number of nuclei of the nuclide gradually decreases. The time required to decay to only half of the original mass is called the half-life of the nuclide. Each radionuclide has a specific half-life, ranging from a few microseconds to millions of years.
A phenomenon in which an atomic nucleus becomes a new nucleus due to the emission of a certain particle. The nucleus is a quantum system. Nuclear decay is a spontaneous change of the nucleus. It is a quantum transition process and it obeys the laws of quantum statistics. For any radionuclide, the precise moment of its decay is unpredictable, but as a whole, the law of decay is very clear. If the number of nuclear decays in the dt time interval is dN, it must be proportional to the number of atomic nuclei N present at that time, and obviously also proportional to the time interval dt.
There are three types of decay: alpha decay, beta decay and gamma decay.
Nuclear fission
Nuclear fission refers to the splitting of a nucleus into several nuclei. Nuclear fission is usually caused by neutrons bombarding the nucleus with a larger mass. After the nucleus fission, two parts of equal mass are formed and energy is released, sometimes resulting in a chain The reaction occurred. Energy = mass ╳ speed of light squared