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Protecting Humans from the Harmful Effects of Radiation
Published in Robert E. Masterson, Nuclear Engineering Fundamentals, 2017
An entirely different class of radiation detector is the scintillation detector or the scintillation counter. The scintillation counter detects radiation by counting the number of photons (or particles or light) that a material emits when it is exposed to a particular type of radiation. There are many different types of scintillation detectors in widespread use today. In this section, we would like to briefly describe how some of the more popular scintillators work. The first scintillation detector was invented by Wilhelm Roentgen in 1895, although it was not recognized as the beginning of a new line of radiation detectors at the time. Roentgen used a scintillating barium platinocyanide plate to discover the existence of x-rays at the time. However, many other materials are also sensitive to various types of radiation, and they will emit photons whenever they are bombarded by a specific type of radiation. Not all of these light waves are visible, but they can easily be counted using a variety of photodetectors that are available today. Many lists of companies that manufacture these types of instruments can be found on the Internet.
Light Sources
Published in Toru Yoshizawa, Handbook of Optical Metrology, 2015
Scintillation counters measure ionizing radiation and are used in high-energy physics experiments for timing, for fast event selection, or for measuring the energy of charged particles by total absorption in sampling calorimeters. Each charged particle passing through the scintillator produces a flash, as the intensity of the light flash depends on the energy of the charged particles. The scintillation counter apparatus consists basically of a scintillator and a photomultiplier with the counter circuits. A scintillation counter can be used also as a spectrometer to determine the energy of x-ray or γ-photons causing scintillation by measuring the intensity of the flash (the number of lower energy photons produced by the high-energy photon). Cesium iodide (CsI) in crystalline form is used as the scintillator for the detection of protons and α-particles, while sodium iodide (NaI) containing a small amount of thallium is used as scintillator for the detection of γ-particles.
Radioactivity investigation of water and aerosols in Sharjah, United Arab Emirates
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2019
Muhammad Zubair, Amrou Ismail, Hamad Mohammed, Sayed Azam, Ahmed Ishag
Measurements of natural background radiation have been carried in numerous parts of the world using a variety of techniques involving the use of gas-filled detectors, spectrometers, etc. Accordingly, in order to determine the tritium level, a scintillation counter has been used. This device operates by detecting the electrons emitted by tritium. These electrons interact with scintillation medium, thus transferring their energy to it. Excited atoms emit gamma rays to return to their ground state. The photodetector detects those gamma rays. It is vital to mention that the sample that has mixed with the scintillation cocktail vial to obtain a homogeneous medium, where the photodetector emits pulses that are amplified, sorted and analyzed by the system. That given to the software to compute the number of counts of the photons which is related to the sample activity. By placing an empty sample in the scintillation counter, background radiation was measured and accounted for.