Gamma radiation is a decaying emission of pure energy. Gamma decay is the form of nuclear decay that is pure energy. There are three other forms of decay, alpha decay, beta decay, and positron emission. Alpha decay releases an alpha particle or a part of the nucleus made up of two protons and two neutrons.
Beta decay releases a beta particle that is a high-energy electron. Positron emission is a type of beta decay but releases a positron or a positively charged electron. In gamma decay, shown in Fig. The number of protons (and neutrons) in the nucleus does not change in this process, so the parent and daughter atoms are the same chemical element.
In the gamma decay of a nucleus, the emitted photon and the receding nucleus each have a well-defined energy after decay. The characteristic energy is divided between only two particles. Another common decay process is the emission of beta particles or beta decay. A beta particle is simply a high-energy electron that is emitted from the nucleus.
It may occur to you that we have a logically difficult situation here. Nuclei contain no electrons, and yet during beta decay, an electron is emitted from a nucleus. At the same time that the electron is ejected from the nucleus, a neutron becomes a proton. It's tempting to imagine it as a neutron that breaks into two parts, the pieces being a proton and an electron.
It would be convenient for the sake of simplicity, but unfortunately this is not the case (more on this topic will be explained at the end of this section). For convenience, we will treat beta decay as a neutron that splits into a proton and an electron. The proton remains in the nucleus, increasing the atomic number of the atom by one. The electron is ejected from the nucleus and is the radiation particle called beta.
When studying nuclear reactions in general, there is usually little information or concern about the chemical status of radioactive isotopes, because electrons in the electron cloud are not directly involved in the nuclear reaction (unlike chemical reactions). The sources of gamma decay are unstable nuclei that already undergo alpha and beta decay or due to other nuclear processes such as neutron capture in a nuclear reactor. In a nuclear explosion or some type of nuclear accident, in which radioactive emitters are dispersed throughout the environment, the emitters can be inhaled or ingested with food or water, and once the alpha emitter is inside you, you have no protection whatsoever.