What is gamma radiation?

Gamma radiation is a form of electromagnetic radiation with the shortest wavelength and highest energy.

Gamma radiation is part of the electromagnetic spectrum, which also includes radio waves, microwaves, infrared, visible light, ultraviolet, and X-rays. It has wavelengths less than 0.01 nanometres, making it the most energetic form of electromagnetic radiation. Gamma rays are produced by the decay of atomic nuclei in a process known as radioactive decay. This often occurs in elements like uranium and radium, or during nuclear reactions such as those in the sun or other stars.

Because of their high energy, gamma rays can penetrate most materials, including human tissue, which makes them both useful and dangerous. In medicine, gamma rays are used in radiotherapy to target and kill cancer cells. They are also used in diagnostic imaging, such as PET scans, to help doctors see inside the body. However, exposure to high levels of gamma radiation can damage living cells and DNA, potentially leading to radiation sickness, cancer, or other health issues.

Gamma radiation is detected using instruments like Geiger-Müller counters, scintillation detectors, and semiconductor detectors. These devices help scientists and medical professionals measure radiation levels and ensure safety standards are met. In industry, gamma rays are used for non-destructive testing to inspect the integrity of materials and structures, such as pipelines and aircraft components.

Understanding gamma radiation is crucial for harnessing its benefits while minimising its risks. By studying how gamma rays interact with matter, scientists can develop better protective measures and more effective applications in medicine, industry, and research.