gamma rays

Paul Villard, a French chemist and physicist, discovered gamma rays in 1900 when experimenting with radium. In 1903, Ernest Rutherford invented these gamma rays based on their capability of solid penetration of matter; by 1900 he had already named two less penetrating types of decay (discovered by Henri Becquerel) alpha and beta rays with increasing penetrating power.

Gamma rays from radioactive decomposition range in energy from a few kiloelectron volts (keV) to approximately 8 megaelectronvolts (~ 8 MeV), corresponding to normal energy  levels in nuclei with long life times.

Gamma rays have a much shorter wavelength and energy than any other wave in the electric spectrum. In general gamma rays are produced by the hottest and most energetic objects in the universe, such as neutron stars, supernova explosions, and regions around black holes. Globally, gamma rays are produced by nuclear explosion, lightning, and very little radioactive decomposition or radioactive decay .

Gamma ray (g) basically is an electromagnetic energy (photon) that is emitted by the nucleus of certain radionuclides following radioactive decomposition. Gamma photons are very powerful photons in the electromagnetic spectrum.

Gamma-ray sources and effects

Fusion, fission, alpha decay, and gamma decay are the four nuclear processes that release gamma rays.

The reaction that fuels the sun and stars is nuclear fusion. It happens through a multistep process in which four protons, or hydrogen nuclei, are forced to fuse into a helium nucleus, which consists of two protons and two neutrons, at severe temperature and pressure. The helium nucleus that results is about 0.7 percent lighter than the four protons that started the reaction. According to Einstein’s famous equation E=mc2, the mass difference is turned into energy, with around two-thirds of that energy released as gamma-rays.

When a star runs out of hydrogen fuel in its final stages of existence, it can use fusion to create successively more massive elements, up to and including iron, but these processes produce less energy with each step.

Nuclear fission is another common source of gamma rays. Nuclear fission is defined by Lawrence Berkeley National Laboratory as the splitting of a heavy nucleus into two roughly equal portions, which are subsequently nuclei of lighter elements. Heavy nuclei, such as uranium and plutonium, are broken down into lesser elements, such as xenon and strontium, in this process, which involves collisions with other particles. The particles created by these collisions can then collide with more heavy nuclei, causing a nuclear chain reaction. Because the combined mass of the resultant particles is less than the mass of the initial heavy nucleus, energy is liberated. According to E=mc2, the mass difference is transformed to energy in the form of kinetic energy of smaller nuclei, neutrinos, and gamma rays.

Uses of Gamma Rays 

Gamma-ray radionuclides are the most widely used radiation sources. In General the  Gamma rays can come in many applications. However, although gamma rays penetrate many objects, this does not cause radiation.

The three most useful radionuclides are cobalt-60, caesium-137, technetium-99m and americium-241.

Properties of Gamma-Rays

There Are Following Property of Gamma Rays:

• In General Gamma-rays are not deflected by any electric and magnetic fields. This property shows it does not have any charge.
• Basically Gamma-rays are electromagnetic waves like X-rays.
• The mass of a Gamma-ray photon is zero.
• Gamma-rays are very fast in General it travel with the speed of light.
• Gamma-rays have very large penetrating power. They can penetrate through several things.
• Gamma-rays produce fluorescence in a substance like willimite.
• It can produce nuclear reactions.
• Basically Gamma rays have small ionizing power.

Conclusion

The term gamma ray was coined by British physicist Ernest Rutherford in 1903 after a study of radioactive emission was performed. Just as atoms with different levels of energy are associated with different configurations of rotating electrons, the atomic nuclei has energy levels that are determined by the formation of protons and neutrons that form the nuclei. 

Although the energy difference between atomic energy levels is usually in the range of 1- to 10-eV, the energy difference in the nuclei usually falls to 1-keV (thousand electron volumes) to 10-MeV ( electron million volts).

When the nucleus undergoes a transition from a high energy level to a low energy level, photons are released to release extra energy; the difference in nuclear energy level is related to the photon waves in the gamma-ray area.