Gamma decay is a type of radioactive decay in which an excited atomic nucleus releases excess energy by emitting a gamma ray, which is a high-energy photon. Unlike alpha or beta decay, gamma decay does not change the number of protons or neutrons in the nucleus; instead, it moves the nucleus from a higher-energy state to a lower-energy or ground state.
How Gamma Decay Works:
- After processes like alpha or beta decay, the daughter nucleus is often left in an excited state with extra energy.
- To reach a more stable configuration, the nucleus emits a gamma photon carrying away this excess energy.
- Gamma rays have very short wavelengths and high penetrating power, making them highly energetic electromagnetic radiation.
Key Characteristics:
- No change in atomic number or mass number; the nucleus only loses energy.
- Gamma emission often accompanies other types of radioactive decay.
- The emitted gamma rays are pure energy, with no charge or mass.
Applications and Importance:
- Gamma rays are used in medical treatments (radiotherapy), industrial radiography, and nuclear imaging.
- Understanding gamma decay helps in nuclear structure studies and radiation safety.
- Gamma decay contributes to the natural background radiation on Earth.