The gamma radiations are constituted by photons, characterized by their energy, inversely proportional to their wavelength. It’s based on principles of collaboration, unobstructed discovery, and, most importantly, scientific progression. 1. Gamma rays can also kill cancer cells, as well as bacteria on food, and can be used as a medical tracer. are summarized in Table 3 . In this chapter, we are presenting a method that we have developed, this which allows us control and calibrate the activation analysis experiments [13]. This chapter is distributed under the terms of the Creative Commons Attribution 3.0 License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Gamma rays are high-energy photons (about 10 000 times as much energy as the visible photons),; The same photons as the photons forming the visible range of the electromagnetic spectrum – light. There are lights like an electric bulb, fireworks and other sources of light rays, with their shiny rays, we can see things and make a dark room visible. The total linear attenuation coefficient, μ compound or mixture of the compound or mixture can then be simply found by multiplying the total mass attenuation coefficient, (μ/ρ)compound with its density, ρ. light-years of Earth. When a narrow beam of N0 (number of photons/unit area) monoenergetic photons with energy E0 passes through an homogeneous absorber of thickness x, the number of photons that reach a depth (in cm) without having an interaction is given by: where μ (in cm) is the linear attenuation coefficient for material of physical density (in g/cm3) and atomic number Z. The energy of gamma rays, as electromagnetic quantum waves, is similar to light, but with higher photon energy and shorter wavelength. In the first part of the chapter, a careful study of the correcting factors linked to the environmental and experimental conditions is performed. Among thousands of gamma emitters only Cobalt-60 is indicated for sterilization processing. X-rays are a type of electromagnetic rays, which are used for medical purposes, and gamma rays are widely used in observational astronomy. This method consists of simulating the process of interaction of gamma rays induced by irradiation of various samples. Gamma-rays are … When struck by cosmic rays, chemical elements in soils and rocks emit uniquely identifiable signatures of energy in the form of gamma rays. The different parameters of the nuclear reactions used (cross section, isotopic abundance, etc.) may occur once every several hundred million years within a few thousand But, by radiating the electrons lose energy: their lives are therefore limited. Nucleus de-excitation: Just like an atom or a molecule, a nucleus has energy levels whose transitions between the least excited levels give rise to gamma radiation. This small difference (in the order of 3%) can be explained by the fact that the nominal values for capsule thickness have been used instead of the mean values which take into account geometry, also to a lesser extent by the fact that self-absorption has not been taken into account in our calculation. What we call "light" is actually just a tiny fraction of the broad range of radiation on the electromagnetic radiation spectrum. The key difference between gamma rays and X-rays is how they are produced. Electromagnetic radiation vanishes brutally as a result of interaction. The total attenuation coefficients are calculated by using respectively the Klein-Nishina theory formula [12], Allen Brodsky’s approximation [15], and Max Born’s approximation [16], for the Compton, photoelectric and pair production effects. To make lasers for use in a surgery room Unlike gamma radiation, E-beams use an on-off technology and provide a much higher dosing rate than gamma or X-rays. Login to your personal dashboard for more detailed statistics on your publications. Gamma rays ionize living tissue, causing cancer … In those situations, a gamma ray source is placed into the substance flowing through the pipe. Gamma-ray telescopes use a process called Compton scattering, began to record bursts of gamma-rays -- not from Earth, but from They are used to treat malignant tumours in radiotherapy. By making research easy to access, and puts the academic needs of the researchers before the business interests of publishers. Gamma rays were first detected from astronomical sources in the 1960s, and gamma-ray astronomy is now a … The induced gamma activities on the sodium, potassium, chlorine and phosphorus elements have been experimentally measured by means of hyper-pure germanium spectrometer. To date our community has made over 100 million downloads. It is therefore a much lighter and less demanding procedure in computer time than the Monte-Carlo method for a similar definition. The leak will be identified wherever the count on the Geiger-Muller tube spikes, indicating a large presence of gamma radiation coming out of the pipes. Scientists believe that a gamma-ray burst In 1967, Available from: Faculty of Sciences Semlalia, University Cadi Ayyad, Morocco, Nuclear Reactor and Nuclear Security, Faculty of Sciences, University Mohammed V, Morocco. is today radio-sterilized by specialized industrialists. The radionuclides measured by this method emit gamma photons of specific energies and their interactions with the detector depend on several variables (geometry or conditioning: physical shape of the object, density, measured quantity, container type, emission energy, size, shape, nature of the detector, etc.). Detectors on board The use of gamma rays in medicine continues to be the primary method of treatment in the field of oncology. Instruments aboard high-altitude balloons and satellites like the In many alpha and beta transitions, the residual nucleus is formed in an excited state. The physicists who have faced this problem, for a long time, have always used methods of statistical or non-statistical computation: Parallel beam methods, Monte-Carlo method and many other methods. Then, someone with a Geiger-Muller tube above-ground will measure the radiation given off. Though gamma rays are bio-hazardous in nature, they can be controlled and used for various important purposes: It is used in the treatment of cancer without surgery. Computed spectra of secondary γ-rays from 40K after 1, 2, 5, 10 Compton interactions [5]. magnetic pulsar flashing every 0.33 second in radio waves. The total linear attenuation coefficient can be decomposed into the contributions from each above described mode of photon interaction as: where μph,μC,μcohandμpare the attenuation coefficient for photoelectric effect, Compton scattering, Rayleigh scattering and pair production respectively. The most intense sources of gamma rays are radioactive sources. reflected in mirrors. Figure 1 shows the linear attenuation of solid sodium iodide, a common material used in gamma-ray detectors. For a copper capsule, the difference of ε between dry a soil and moderately wet (e.g., less than 15% water) is negligible (less than 1%); therefore, it is not necessary in this case to know exactly the soil humidity to perform the correction, which is an advantage. Our readership spans scientists, professors, researchers, librarians, and students, as well as business professionals. In the case of water, a “light” medium and a strong low energy ray contribution (below 100 keV) can be noticed. events as supernova explosions or the destruction of atoms, and by less Computed energy spectra for 40K in (a) dry C soil, (b) wet S soil, and (c) pure water [5]. In astrophysics, detection of gamma rays can provide a lot of information about the bodies that produce them. *Address all correspondence to: hassane@uca.ac.ma, Use of Gamma Radiation Techniques in Peaceful Applications. The development of γ-spectrometry began with the development of nuclear sciences and technology to meet the needs for the control, characterization and analysis of radioactive materials. The detection of gamma rays require a special kind of detector, called gamma rays telescope which the uses Compton Scattering process to detect gamma rays. They have many of the same uses as X-rays, including cancer therapy. The gamma-ray moon just looks like a The third group will include it isotopes created by external causes, such as the interaction of cosmic rays with the earth and its atmosphere. However, in most cases, the contribution of these three radioelements does not exceed 60% and approximate values on the whole with acceptable dispersion may be proposed. The β-decay of the 60Co to 60Ni produces a double radiation emission of 1.17 and 1.33 MeV. Figure 4 an example of various order spectra for 40K. This program results in determining the energy loss predominant phenomenon that occurs when gamma rays interact with the absorber. The interactions of gamma rays with the material taken into consideration are the photoelectric effect and the Compton effect; the pair production is considered negligible to the considered energies (<2.6 MeV). We are IntechOpen, the world's leading publisher of Open Access books. Three types of radiations are emitted from radioactive elements that are Alpha, Beta, and Gamma radiations. Spectrometry γ then became a powerful tool for studying decay patterns. There is a similarity in the degraded spectrum, even for two very different gamma sources (for example, thorium and potassim-40). This is due to a smaller contribution of low energies to the 40K spectrum (no low energy lines). *Response times vary by subject and question complexity. Cancers cells divided more quickly are more sensitive, than normal cells to ionizing radiation. What gamma rays are and their sources, and the dangers and uses of gamma rays. X-rays and gamma rays are created in power plants for nuclear energy, and are also used in smaller amounts for medical imaging tests, cancer treatment, food irradiation, and airport security scanners. By Seyed Mahyar Mirmajlessi, Hossein Ahari Mostafavi, Evelin Loit, Neda Najdabbasi and Marika Mänd. Lead shielding surrounding the reactor ... said on his blog. For the uranium series, the contribution of uranium-235 and its descendants were taken into account. Gamma rays used for sterile processing are formed with the self disintegration of Cobalt-60 (60Co). The attenuation coefficient is the sum of coefficients of the various interaction modes (Compton, photoelectric, pair production), the proportion of each of these effects varying with the radiation energy and nature of the absorber. Calculations are performed here with, as a TL dosimeter, CaSO4: Dy, but are readily feasible for any combination of known dosimeters and compositions. The high energy of gamma rays enables them to pass through many kinds of materials, including human tissue. Uses of gamma radiation. After one interaction, the energy spectrum of secondary γ-rays will be: And the ratio of secondary to primary γ-rays is: In the same way, the spectrum of third generation γ-rays can be deduced from N2 (E), and in a more general manner the following recurrence relations hold: Of course, there is a rapid decrease with i of the mean γ energy and of the total energy carried. Figure 2 shows the relationship between the linear attenuation coefficient and the HVL for a soft tissue [3]. So It can be found that ε it may be less than or greater than 1; two antagonistic effects act: on the one hand, the absorption by the walls, which tends to decrease ε on the other hand, the difference in nature between soil and TL dosimeter which has the opposite effect, the coefficient of absorption of the dosimeter being the highest. GAMMA RAY SKY. Things like supernova explosions (the way massive stars die), neutron And for 232Th in pure water ( Figure 6 ). Irradiation of art objects: Treatment with gamma rays helps to eliminate larvae, insects or bacteria lived inside objects, to protect them from degradation. The average distance between two successive interactions is called the relaxation length (λ) or the photon mean free path which is determined by the equation: where μ is the linear attenuation coefficient and x is the absorber thickness. These spectra show the overlapping of the primary ray spectrum and the degraded continuous spectrum, which carry most of the energy (60%). Gamma rays When gamma rays are used as medical tracers, a chemical containing the rays is injected into the body of a patient. Various uses of gamma-rays are outlined below: Gamma rays are used as a disinfectant in industries. Gamma rays are the result of the radioactive decay of the nucleus of an atom. By solving the mystery of gamma-ray bursts, scientists hope to gain further The many forms of radiation that are used include electromagnetic waves of widely differing wavelengths (e.g., radio waves, visible light, ultraviolet radiation, X rays, and gamma rays), as well as particulate radiations of various types (e.g., electrons, fast neutrons, protons, alpha particles, and pi-mesons). Similar to X-rays, gamma rays can get past even some of the densest materials in use, making them both a great benefit and a hazard. The uniform random sampling of the emission point P1 and emission direction is achieved by computing the distance from the center r1, the depth t, cos(θ) and ψ, with four uniform random numbers [17]: We have developed the following theory to calculate the path length 12 which is given by: h is the distance between the sample and the detector ( Figure 7 ). Thus, energy electrons 3 × 108 MeV in a magnetic field of 3 × 10−6 Gauss will create a gamma radiation. They are also produced by such violent Gamma rays are used in medicine (radiotherapy), industry (sterilization and disinfection) and the nuclear industry. What is the difference between gamma rays and X-rays? The excess energy appears as a kinetic form. However, great care must be taken, because gamma-rays can also damage the DNA of surrounding healthy tissue cells.One way to maximize the dosage to cancer cells while minimizing the exposure to healthy tissues is to direct multiple gamma-ray beams from a linear accelerator, or linac, onto the target region from many different directions. The book covers an … Uses Because Gamma rays can kill living cells, they are used to kill cancer cells without having to resort to difficult surgery. The calculation method has the advantage of being accurate (error is smaller than 3%) and rapid (the calculation time is of about 2 min). Help us write another book on this subject and reach those readers. Gamma Rays Uses The gamma rays have several uses. 0 8,590 5 minutes read. The dispersal of the value of ε is smaller between the different soil for a copper capsule than for a polyethylene capsule. For treatment deep within the body, high energy photons are sent to reach the target tumour without affecting the surrounding tissue. The thicker the material, the more radiation is absorbed and the less radiation reaches the detector. astronomers detected the remnant core of that star; a rapidly rotating, The calculation of ε was done for the list of floors already cited (from the gamma ray energy spectra already calculated), for the three radiation sources and for two types of 1 g/cm2 thick absorbers, sufficient to stop beta radiation. Gamma rays are formed with the self disintegration of Cobalt-60 (60Co) or Cesium-137 (137Cs) sources. On the other hand, the degraded spectrum is higher in energy as the of the medium is high: this is due to the increasing influence of the photoelectric effect which “cuts” the low gamma ray energy. For the use of these formulas, it is assumed that there is an electronic equilibrium, that is, the dimensions of the dosimeter are equal to or greater than the secondary electron range (of the order of a few mm). The first gamma-ray telescope carried into orbit, on the Explorer 11 satellite in 1961, picked up fewer than 100 cosmic gamma-ray photons. 2)It is used in industries to kill the harmful bacteria, organism like yeast etc. Gamma rays. Just like gamma rays, x-rays can’t be seen, felt or heard. photons! Although a large number of possible interaction mechanisms are known, when monoenergetic gamma rays are attenuated in the matter, only four major effects are important: photoelectric effect, Compton effect, elastic or Rayleigh scattering and pair production (with a threshold energy of 1022 keV). Explorer XI satellite in 1961, picked up fewer than 100 cosmic gamma-ray On the other hand, we are presenting a calculation method for controlling neutron activation analysis (NAA) experiments. The linear attenuation coefficient is inversely proportional to a quantity called a half-value layer (HVL), which is the material thickness needed to attenuate the intensity of the incident photon beam to half of its original value. They pass through most types of materials. Gamma-rays can kill living cells, a fact which medicine uses to its advantage, using gamma-rays to kill cancerous cells. Gamma rays are a form of electromagnetic radiation, whereby gamma radiation kills microorganisms by destroying cellular nucleic acid [1]. (9) is only approximate and a more exact formulation is: where μ02 and σ02 are, respectively the total and Compton mass attenuation coefficients for the encapsulating material; F(E, E’) is the energy distribution of secondary γ-rays (energy E’) from a Compton interaction induced by a photon of energy E. F(E, E’) can be obtained from the well-established Klein and Nishina cross-section for Compton effect [11]. 105 years « normal » value elements in soils and rocks emit uniquely identifiable signatures of currently! Perhaps the most widely used increased risk for birth defects when they deliver in nuclear medicine mm... Correspondence to: hassane @ uca.ac.ma, use of gamma emitters only 137Cs and 60Co are indicated sterilization! 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Or from the annihilation of positron with electrons 2 shows the linear attenuation coefficient of the element cobalt cobalt... Like a round blob - lunar features are not visible medium with 1 g m−2 capsule wall thickness 5. On principles of collaboration, unobstructed discovery, and pair production 1 ] a common used...