Gamma radiation, a constituent of photons, is a high-energy electromagnetic emission resulting from the radioactive decaying atomic nuclei. This ionizing radiation has shorter wavelengths with greater penetration that can only be blocked by thick lead block or concrete block.
Paul Villard, a French physicist, discovered gamma radiation in 1900. Its applications include sterilization of medical equipment and treatment of cancer.
History of Gamma Radiation
Paul Villard’s discovery came about as he was studying the radium element’s radiation emission. However, it was not until 1903 that Ernest Rutherford gave the new radiation discovery the name ‘gamma’ following beta and alpha radiations previously discovered in 1896 and 1899, respectively.
The new form of radiation (gamma) was found to have high energy compared to the other two. Gamma radiation’s photons were found to have energy levels higher than 100keV. The high energy levels allow gamma radiation to penetrate matter easily. Due to the potential hazard to human health, gamma radiation is detected and monitored using hi-tech tools such as Cadmium.
Sources of Gamma Radiation
Gamma radiation can either be produced naturally or artificially. The artificial sources of gamma radiation include nuclear fission. This is the splitting of heavy nuclei such as plutonium or uranium into lighter elements.
Natural sources of gamma rays, on the other hand, can be divided into 3 large groups, depending on their original elements. The first consists of Thorium, Potassium, and Uranium, while the second is made up of radioactive isotopes of the first. A 3rd group combines all the other external sources of gamma rays, such as the collision of cosmic rays with matter.
These sources can be summarized as follows:
- Gamma Decay
- Annihilation of antimatter
- Lightning
- Solar flares
- Cosmic rays
- Collision of stars.
Application of Gamma Radiation
Nuclear energy is commonly applied in the production and supply of electricity. Radioactivity applications span across various sectors, including earth sciences, medical physics, preservation of cultural heritage and industries.
Gamma radiation is applied widely because of the following properties:
- Radiation emission
- Time of decline of radioactivity
- Sensitivity of detection.
Gamma Radiation in Medicine
Gamma radiation is pivotal in medicine because of its utilization in radiotherapy – targeted destruction of cancer cells by ionizing radiation.
Cancerous cells subdivide quickly. This makes them more sensitive to ionizing radiation. In radiotherapy, a measured dose of radiation is administered to the targeted tumor area with the potential of killing these cells and, therefore, eliminating the tumor.
Medical sterilization of equipment and food irradiation
Gamma irradiation is used to sterilize tools and objects to get rid of potential disease-causing fungi, viruses, and bacteria. Most surgical equipment is cleaned through sterilization using gamma rays.
Moreover, to improve food hygiene, gamma rays are used through what is known as food irradiation. This eliminates salmonella and other causes of food poisoning.
Conservation of art and cultural objects
The penetrating power of gamma rays enables it to be used to eliminate insect’s larvae and bacteria that may be accumulating inside or outside art and cultural objects. This method of irradiation helps conserve these objects and maintain their value over a long period.
Besides, its application in the conservation and restoration of these objects is possible because of its applicability with different materials such as stone, leather, and wood.
Conclusion
Gamma radiation has always been present in our environment. Its effect on our health makes it necessary to monitor and control its application, hence the need for tools such as Cadmium. However, since its discovery in 1900, the controlled exploitation of this form of radiation has resulted in useful trends such as treatment of cancer, sterilization of medical equipment, and preservation of art objects.