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Signal Generation in Semiconductor Detectors for Photon-Counting CT
Published in Katsuyuki Taguchi, Ira Blevis, Krzysztof Iniewski, Spectral, Photon Counting Computed Tomography, 2020
Xiaochun Lai, Liang Cai, Kevin Zimmerman, Richard Thompson
Compton scattering and the photoelectric interaction will transfer either part or all of the photon energy to the interacted electron. The electron loses its energy through scattering, ionization of atoms, and Bremsstrahlung radiation. Consequently, the interaction generates phonons (lattice vibration) or electron-hole pairs in CdTe or CZT. The process of the electron-hole pair (Neh) generation could be modeled as a Poisson process. Since the number of electron-hole pairs is on the order of 10,000, the process could be approximated by a Gaussian distribution: P(Neh)=12πFN¯ehexp−(Neh−N¯eh)22FN¯eh,
Theoretical Consideration of the Response Function of a Two-Dimensional CdTe Detector
Published in Salim Reza, Krzysztof Iniewski, Semiconductor Radiation Detectors, 2017
The Compton scattering effect is the interaction between photons and free electrons. In this situation, we should consider the conservation laws of energy and momentum between these two particles. A schematic drawing of the Compton scattering effect is shown in Figure 4.9. The equations for conservation laws can be solved analytically. The energy of scattered photons (hν′) is described as
High-Energy (X-Ray and γ-Ray) Photon Interactions with Matter
Published in Harry E. Martz, Clint M. Logan, Daniel J. Schneberk, Peter J. Shull, X-Ray Imaging, 2016
Harry E. Martz, Clint M. Logan, Daniel J. Schneberk, Peter J. Shull
The photon angular distribution in polar coordinates for Compton scattering at three incident photon energies is given in Figure 5.13. We see from Figure 5.13 that Compton scattering becomes more forward peaked with increasing photon energy. This means that at the highest energies used for imaging, most Compton scattering events result in scattered x-rays that have been slightly deflected and have slightly reduced energy.
Gamma ray characterization of the albedo of atmospheric dust from Southeast Anatolia, Turkey
Published in Instrumentation Science & Technology, 2021
Tuba Rastgeldi Dogan, Demet Yilmaz, Serife Yalcin
Albedo is an important concept in climatology, astronomy, and environmental management. The fraction of the incident electromagnetic radiation which the surface reflects is the albedo of a surface. Albedos may change depending on the surface. [10,11] The reflections from oceans, lakes, and forests are not high and therefore they do not have high albedo values.[12] Albedo parameters are also used to determine the physical properties of technologically important materials.[13] Albedo parameters may be calculated from Compton and coherent scattering. Compton scattering is the scattering of a photon of high energy from an electron considered to be free and stationary or from an atomic electron whose binding energy is small compared with the incident photon energy. Coherent scattering is the elastic scattering of electromagnetic radiation by a free charged particle, and the particle's kinetic energy and photon frequency do not change due to the scattering.
Importance of Voxel Size in Defect Localization Using Gamma-Ray Scattering
Published in Nuclear Science and Engineering, 2019
Akash Tondon, Mohinder Singh, B. S. Sandhu, Bhajan Singh
Compton scattering, the interaction of X-ray or gamma photons with electrons of the target material, results in scattering of incident photons with reduced energy. This process is the dominant mode of interaction in the intermediate-energy (100 keV to 1 MeV) region. The inherent ability of Compton scattering can ascertain quantitative information of the electron density of the material to be interacted. According to Compton scattering theory, the number of scattered photons at an angle θ is given by
A Feasibility Study on the Transmutation of 100Mo to 99mTc with Laser-Compton Scattering Photons
Published in Nuclear Technology, 2018
Jiyoung Lee, Haseeb ur Rehman, Yonghee Kim
The mathematical formulation of the differential Compton scattering cross section in the electron rest frame of reference is based on the Klein-Nishina cross section.12 This model can then be translated to the laboratory frame and is expressed in Eq. (3):