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In this paper, we study the couplings of the gravity supermultiplet (graviton and gravitino) of minimal 풩=1 supergravity (SUGRA) following a constructive approach. First, we use the master formula that follows from considering the scaling behavior of the spinor variables under the little group. Second, we derive the four-point couplings using the Britto–Cachazo–Feng–Witten (known as BCFW) recursion relations. Then, we verify these results for the general three-point interactions that can be derived using the Kawai–Lewellen–Tye relations (also known as KLT-type relations), i.e. they can be written as the square of the coupling of the gluons and gluinos. Finally, we consider the graviton–gravitino SUGRA Compton effect. For completeness, we present in the appendix the 풩=1 SUGRA Lagrangian in the two-component Weyl formalism, including proofs of supersymmetry (SUSY) and gauge invariances. [ABSTRACT FROM AUTHOR]

A model of a dynamical three-dimensional quantum vacuum based on energy fluctuations of a granular space is considered as the keystone able to provide a unifying rereading of microphysics and macrophysics. By starting from a generalized version of uncertainty relations, a generalized Compton wavelength is defined that provides a unifying treatment of elementary particles and black holes. A quantum-modified Schwarzschild metric associated with the generalized Compton wavelength of the vacuum is introduced and its perspectives in providing a new rereading of the standard general relativistic predictions for light deflection, perihelion precession, and gravitational redshift are explored. [ABSTRACT FROM AUTHOR]

In this paper, the gamma radiation attenuation parameters were calculated using Phy-X/PSD for a prepared quaternary system of phosphate glass (95-x)P2O5-xBi2O3-3Na2SO4-2ZnO, where (x = 30, 40, and 50 mol%). In addition, the attenuation interactions were calculated using the X-Com program, as all these calculations were done in the range of energies (0.1–3 MeV). The results showed that the S3 sample had the highest value of the mass attenuation coefficient up to the energy value of 0.8261 MeV, after which the values of the three investigated samples were approximately equal. The S3 sample also has the lowest value for a half value layer during the measured range of energy. The results also showed that the photoelectric effect interaction is the largest contributor to the attenuation process at the first three energies (0.1, 0.15, and 0.2 MeV), and at energy values ​​with 0.3–3 MeV, the Compton effect becomes the largest contributor to the attenuation process. The contribution of the pair production effect interaction begins to appear at the energy 1.025 MeV, and its contribution to the gamma ray attenuation process increases gradually in association with the Compton effect interaction until the value of 3 MeV. [ABSTRACT FROM AUTHOR]

The past 30 years have brought undeniable progress in medicine, biology, physics, and research. Knowledge of the nature of the human body, diseases, and disorders has been constantly improving, and the same is true regarding their treatment and diagnosis. One of the greatest advances in recent years has been the introduction of nanoparticles (NPs) into medicine. NPs refer to a material at a nanometer scale (0.1–100 nm) with features (specific physical, chemical, and biological properties) that are broadly and increasingly used in the medical field. Their applications in cancer treatment and radiotherapy seem particularly attractive. In this field, inorganic/metal NPs with high atomic number Z have been employed mainly due to their ability to enhance ionizing radiation's photoelectric and Compton effects and thereby increase conventional radiation therapy's efficacy. The improvement NPs enable relates to their enhanced permeation ability and longer retention effect in tumor cells, capacity to reduce toxicity of commercially available cancer drugs through advanced NPs drug delivery systems, radiation sensitizers of tumors, or enhancers of radiation doses to tumors. Advanced options according to size, core, and surface modification allow even such multimodal approaches in therapy as nanotheranostics or combined treatments. The current state of knowledge emphasizes the role of gold nanoparticles (AuNPs) in sensitizing tumors to radiation. We have reviewed AuNPs and their radiosensitizing power during radiation treatment. Our results are divided into groups based on AuNPs' surface modification and/or core structure design. This study provides a complete summary of the in vivo sensitizing effect of AuNPs, surface-modified AuNPs, and AuNPs combined with different elements, providing evidence for further successful veterinarian and clinical implementation. [ABSTRACT FROM AUTHOR]

High‐sensitivity wearable radiation detectors are essential for personnel protection in radiation environments such as defense, nuclear facilities, and medical fields. Traditional detectors using bulk crystals lack flexibility, and emerging perovskite films suffer from lead toxicity and poor charge transport. Herein, lead‐free photoferroelectric hybrid metal halide perovskite flexible membranes for wearable detectors are presented, offering superior X‐ray response with sensitivities up to 7872 ± 517 µC Gyair−1 cm−2 at 50 V bias and 394 ± 67 µC Gyair−1 cm−2 in a self‐driven mode, detection limit of lower than 77 nGyair s−1, and excellent imaging capabilities. This exceptional performance is attributed to the spontaneous polarization that promotes efficient charge transport. Additionally, they show remarkable radiation stability, long‐term air stability, mechanical fatigue resistance, and water stability. They also exhibit efficient energy response under the Compton effect and meet the angle response requirements of the International Electrotechnical Commission standard for direct‐reading personal dose equivalent meters, paving the way for their integration into flexible, wearable dosimeters. These advancements have the potential to drive the realization of the next generation of flexible wearable radiation detectors. [ABSTRACT FROM AUTHOR]

A four level chiral medium is considered to analyze and investigate theoretically the reflection/transmission coefficients of right circularly polarized (RCP) beam and left circularly polarized (LCP) beam as well as their corresponding GH-shifts under the effect of compton scattering. Density matrix formalism is used for calculation of electric and magnetic probe fields coherence. The polarization and magnetization are calculated from probes coherence terms in the chiral medium. The electric and magnetic susceptibilities as well as chiral coefficients are related with polarization and magnetization. The refractive indices of RCP and LCP beams under compton scattering effect is modified from the electric/magnetic susceptibilities, chiral coefficients, mass and charge of electron as well as compton scattering angle. The giant positive and negative birefringent Goos–Hänchen (GH) shifts in reflection and transmission beams are investigated in this manuscript under Compton scattering effect. The RCP and LCP beams obey the normalization condition | R (+ , -) | + | T (+ , -) | = 1 at the interface of a lossy chiral medium of | A (+ , -) | ≃ 0 and a thin sheet of balsa wood under the effect of compton scattering angle, incident angle, probe field detuning, control field Rabi frequency, phases of electric and magnetic fields and phase of superposition states. Significant positive/negative giant GH-shifts in reflection and transmission beams are investigated. The results show potential applications in modification of cloaking devices, image coding, polarizing filters and LCD displays. [ABSTRACT FROM AUTHOR]

Background: Edge‐on‐irradiated silicon detectors are currently being investigated for use in full‐body photon‐counting computed tomography (CT) applications. The low atomic number of silicon leads to a significant number of incident photons being Compton scattered in the detector, depositing a part of their energy and potentially being counted multiple times. Even though the physics of Compton scatter is well established, the effects of Compton interactions in the detector on image quality for an edge‐on‐irradiated silicon detector have still not been thoroughly investigated. Purpose: To investigate and explain effects of Compton scatter on low‐frequency detective quantum efficiency (DQE) for photon‐counting CT using edge‐on‐irradiated silicon detectors. Methods: We extend an existing Monte Carlo model of an edge‐on‐irradiated silicon detector with 60 mm active absorption depth, previously used to evaluate spatial‐frequency‐based performance, to develop projection and image domain performance metrics for pure density and pure spectral imaging tasks with 30 and 40 cm water backgrounds. We show that the lowest energy threshold of the detector can be used as an effective discriminator of primary counts and cross‐talk caused by Compton scatter. We study the developed metrics as functions of the lowest threshold energy for root‐mean‐square electronic noise levels of 0.8, 1.6, and 3.2 keV, where the intermediate level 1.6 keV corresponds to the noise level previously measured on a single sensor element in isolation. We also compare the performance of a modeled detector with 8, 4, and 2 optimized energy bins to a detector with 1‐keV‐wide bins. Results: In terms of low‐frequency DQE for density imaging, there is a tradeoff between using a threshold low enough to capture Compton interactions and avoiding electronic noise counts. For 30 cm water phantom, 4 energy bins, and a root‐mean‐square electronic noise of 0.8, 1.6, and 3.2 keV, it is optimal to put the lowest energy threshold at 3, 6, and 1 keV, which gives optimal projection‐domain DQEs of 0.64, 0.59, and 0.52, respectively. Low‐frequency DQE for spectral imaging also benefits from measuring Compton interactions with respective optimal thresholds of 12, 12, and 13 keV. No large dependence on background thickness was observed. For the intermediate noise level (1.6 keV), increasing the lowest threshold from 5 to 35 keV increases the variance in a iodine basis image by 60%–62% (30 cm phantom) and 67%–69% (40 cm phantom), with 8 bins. Both spectral and density DQE are adversely affected by increasing the electronic noise level. Image‐domain DQE exhibits similar qualitative behavior as projection‐domain DQE. Conclusions: Compton interactions contribute significantly to the density imaging performance of edge‐on‐irradiated silicon detectors. With the studied detector topology, the benefit of counting primary Compton interactions outweighs the penalty of multiple counting at all lowest threshold energies. Compton interactions also contribute significantly to the spectral imaging performance for measured energies above 10 keV. [ABSTRACT FROM AUTHOR]

The article presents a theoretical study of Oleinik resonances in the process of scattering a gamma quantum by an ultrarelativistic electron in the field of a strong electromagnetic wave with intensities up to  10 27 Wcm − 2 . The resonant kinematics for three possible resonant reaction channels in a strong external field have been studied in detail. It is shown that under resonant conditions, the scattering channels of the reaction effectively split into two first-order processes according to the fine structure constant, such as the external field-stimulated Compton effect. The annihilation channel of the reaction effectively decays into direct and reverse the external field-stimulated Breit–Wheeler processes. In the absence of interference from the reaction channels, a resonant differential cross-section was obtained in a strong external electromagnetic field. The cases when the energy of the initial electrons significantly exceeds the energy of the initial gamma quanta have been studied. At the same time, all particles (initial and final) fly in a narrow cone away from the direction of wave propagation. The conditions under which the energy of ultrarelativistic initial electrons is converted into the energy of a finite gamma quantum are studied. It is shown that the resonant differential cross-section of such a process significantly (by several orders of magnitude) exceeds the corresponding nonresonant cross-section. This theoretical study predicts a number of new physical effects that may explain the high-energy fluxes of gamma quanta produced near neutron stars and magnetars. [ABSTRACT FROM AUTHOR]

This scientific paper focuses on the treatment of breast cancer, one of the most common cancers among women. Despite increased awareness and the popularity of screening tests, statistics indicate a significant rise in incidence. The paper presents breast-conserving treatment methods, including brachytherapy, as a modern technique with promising outcomes. It describes the physical properties of ionizing radiation used in brachytherapy, discussing the photoelectric effect, Compton effect, and the phenomenon of pair production. The paper then delves into the biological effects of ionizing radiation, emphasizing the dependence on the cell cycle phase. It highlights lethal, sublethal, and potentially lethal cellular damage, categorizing the effects of radiation interaction into early and late responses. The discussion transitions to the application of brachytherapy in breast cancer treatment, focusing on various techniques such as LDR, PDR, and HDR. The paper provides a detailed description of brachytherapy's use in breast-conserving treatment, considering contraindications, treatment planning, and Accelerated Partial Breast Irradiation (APBI) techniques. The radioisotopes used in brachytherapy are also presented, with special attention to Iridium-192. The physical and practical aspects related to this isotope are discussed, along with other commonly used radioisotopes such as Cesium-137, Cobalt-60, and Strontium-90. The paper concludes with a summary, emphasizing the significance of brachytherapy in breast cancer treatment and outlining its prospects for development. The authors highlight precision and shortened therapy duration. Aim of the study The following paper aims to present a review of current knowledge regarding brachytherapy in the treatment of breast cancer and the treatment outcomes associated with this method. The main goal is to raise awareness among healthcare professionals about current issues with improvement of breast cancer treatment procedures based on brachytherapy. Materials and methods This article presents the current state of knowledge about brachytherapy for breast cancer, as found in various scientific articles. The following English keywords and their Polish equivalents were used to search Google Scholar's medical databases: brachytherapy, conservative treatment, breast cancer, BT, MammoSite. The most relevant articles on the subject were selected. [ABSTRACT FROM AUTHOR]

Radiation hydrodynamical equations with Compton scattering are generally difficult to solve analytically, and usually examined numerically, even if in the subrelativistic regime. We examine the equations available in the subrelativistic regime of k B T |$/$| (m e c 2) ≲ 0.1, h ν |$/$| (m e c 2) ≲ 0.1, and v |$/$| c ≲ 0.1, where T is the electron temperature, ν the photon frequency, and v the fluid bulk velocity. For simplicity, we ignore the induced scattering terms. We then seek and obtain analytical solutions of frequency-dependent radiative moment equations of a hot plasma with bulk motions for several situations in the subrelativistic regime. For example, in the static case of a plane-parallel atmosphere without bulk motions, where equations involve the generalized Kompaneets equation with subrelativistic corrections, we find the Wien-type solution, which reduces to the usual Milne–Eddington solution in the nonrelativistic limit, as well as the power-law-type one, which has a form of [ h ν |$/$| (k B T)]−4. In the moving case of an accelerating one-dimensional flow with bulk motions, we also find the Wien-type and the power-law-type solutions affected by the bulk Compton effect. Particularly, in the Wien-type solutions, due to the bulk Compton effect, the radiation fields gain momentum from the hot plasma in the low-frequency regime of h ν < 3 k B T , while they lose it in the high-frequency regime of h ν > 3 k B T. [ABSTRACT FROM AUTHOR]

This paper presents the results of the influence of variation of the synthesis conditions of CuBi/CuBi2O4 films with a change in the applied potential difference, as well as a change in electrolyte solutions (in the case of adding cobalt or nickel sulfates to the electrolyte solution) on changes in the phase composition, structural parameters and strength characteristics of films obtained using the electrochemical deposition method. During the experiments, it was found that, in the case of the addition of cobalt or nickel to the electrolyte solutions, the formation of films with a spinel-type tetragonal CuBi2O4 phase is observed. In this case, a growth in the applied potential difference leads to the substitution of copper with cobalt (nickel), which in turn leads to an increase in the structural ordering degree. It should be noted that, during the formation of CuBi/CuBi2O4 films from solution–electrolyte №1, the formation of the CuBi2O4 phase is observed only with an applied potential difference of 4.0 V, while the addition of cobalt or nickel sulfates to the electrolyte solution results in the formation of the tetragonal CuBi2O4 phase over the entire range of the applied potential difference (from 2.0 to 4.0 V). Studies have been carried out on the strength and tribological characteristics of synthesized films depending on the conditions of their production. It has been established that the addition of cobalt or nickel sulfates to electrolyte solutions leads to an increase in the strength of the resulting films from 20 to 80%, depending on the production conditions (with variations in the applied potential difference). During the studies, it was established that substitution of copper with cobalt or nickel in the composition of CuBi2O4 films results in a rise in the shielding efficiency of low-energy gamma radiation by 3.0–4.0 times in comparison with copper films, and 1.5–2.0 times for high-energy gamma rays, in which case the decrease in efficiency is due to differences in the mechanisms of interaction of gamma quanta, as well as the occurrence of secondary radiation as a result of the formation of electron–positron pairs and the Compton effect. [ABSTRACT FROM AUTHOR]

Background: Silicon (Si) is a possible sensor material for photon counting detectors (PCDs). A major drawback of Si is that roughly two‐thirds of x‐ray interactions in the diagnostic energy range are Compton scattering. Because Compton scattering is an energy‐insensitive process, it is commonly assumed that Compton events retain little spectral information. Purpose: To quantify how much information can be recovered from Compton scattering events in models of Si PCDs. Methods: We built a simplified model of Si interactions including two interaction mechanisms: photoelectric effect and Compton scattering. We considered three different binning options that represent strategies for handling Compton events: in Compton censoring, all events under 38 keV (the maximum energy possible from Compton scattering for a 120 keV incident photon) were discarded; in Compton counting, all events between 1 and 38 keV were placed into a single bin; in Compton binning, all events were placed into energy bins of uniform width. These were compared to the ideal detector, which always recorded the correct energy (i.e., 100% photoelectric effect). Every photon was assumed to interact once and only once with Si, and the energy bin width was 5 keV. In the primary analysis, the Si detector was irradiated with a 120 kV spectrum filtered by 30 cm of water, with 99.5% of the arriving spectrum above 38 keV so that there was good separation between photoelectric effect and Compton scattering, and the figures of merit were the Cramér–Rao lower bound (CRLB) of the variance of iodine and water basis material decomposition images, as well as the CRLB of virtual monoenergetic images (i.e., linear combinations of material images) that maximize iodine CNR or water CNR. We also constructed a local linear estimator that attains the CRLB. In secondary analyses, we applied other sources of spectral distortion: (1) a nonzero minimum energy threshold; (2) coarser, 10 keV energy bins; and (3) a model of charge sharing. Results: With our chosen spectrum, 67% of the interactions were Compton scattering. Consistent with this, the material decomposition variance for the Compton censoring model, averaged over both basis materials, was 258% greater than the ideal detector. If Compton events carried no spectral information, the Compton counting model would show similar variance. Instead, its basis material variance was 103% greater than the ideal detector, implying that Compton counts indeed carry significant spectral information. The Compton binning model had a basis material variance 60% greater than the ideal detector. The Compton binning model was not affected by a 5 keV minimum energy threshold, but the variance increased from 60% to 107% when charge sharing was included and to 78% with coarser energy bins. For optimized CNR images, the average variance was 149%, 12%, and 10% higher than the ideal detector for the Compton censoring, counting, and binning models, reinforcing the hypothesis that Compton counts are useful for detection tasks and that precise energy assignments are not necessary. Conclusions: Substantial spectral information remains after Compton scattering events in silicon PCDs. [ABSTRACT FROM AUTHOR]

A detailed account is given of Arthur Compton's original experiment and subsequent ones by Walter Bothe and Hans Geiger and Compton and Alfred Simon who, conclusively, demonstrated the reality of the quantum of light proposed by Albert Einstein. The article highlights the repercussion and impact that the Compton Effect immediately generated in the physics community in Europe and the United States. In particular, the reactions of Einstein and Bohr are proven, who built, with two other colleagues, the BKS theory in opposition to the idea of the individual scattering of the quantum of light with the electron, as proposed by Compton and, independently, by Peter Debye. The article also discusses how the Compton Effect was introduced in Brazil, which, significantly, was carried out by Einstein himself and Marie Curie. [ABSTRACT FROM AUTHOR]

The Compton scattering effect of electromagnetic waves (photons) on free electrons has been known since the beginning of the twentieth century. A photon moving toward a fast electron can be scattered in the opposite direction, significantly increasing its energy because of the loss of it by the electron. When the scattering electron is not free, but moves in a single crystal in the channeling mode, periodic harmonics of the potential of atomic planes or axes along which the channeled electron moves can serve as the scattered photon. In the so-called accompanying reference system moving at the velocity equal to the longitudinal component of the channeled particle velocity, these harmonics can be considered as electromagnetic waves (equivalent photons) interacting with the electron making finite orbital or oscillatory motion in the averaged potential of the atomic axis or plane. The result of equivalent photon backscattering is a real photon, observable as a high-energy photon in the laboratory system. Because of the discreteness of the transverse motion energy spectrum of the channeled electron, the emitted photon spectrum will also be discrete. This work continues a series of our previous studies [3–5] of effects associated with electromagnetic processes during the passage of fast charged particles through crystal structures within a mixed quantum-classical approach. The backscattering kinematics of photons and equivalent photons by the ultrarelativistic electrons has been analyzed in detail in the general case and in the channeling mode. The characteristic frequencies have been calculated and the intensity of the resulting radiation has been estimated. [ABSTRACT FROM AUTHOR]

The use of ionizing radiation offers a boundless range of applications for polymer scientists, from inducing crosslinking and/or degradation to grafting a wide variety of monomers onto polymeric chains. This review in particular aims to introduce the field of ionizing radiation as it relates to the degradation and recycling of cellulose and its derivatives. The review discusses the main mechanisms of the radiolytic sessions of the cellulose molecules in the presence and absence of water. During the radiolysis of cellulose, in the absence of water, the primary and secondary electrons from the electron beam, and the photoelectric, Compton effect electrons from gamma radiolysis attack the glycosidic bonds (C-O-C) on the backbone of the cellulose chains. This radiation-induced session results in the formation of alkoxyl radicals and C-centered radicals. In the presence of water, the radiolytically produced hydroxyl radicals (●OH) will abstract hydrogen atoms, leading to the formation of C-centered radicals, which undergo various reactions leading to the backbone session of the cellulose. Based on the structures of the radiolytically produced free radicals in presence and absence of water, covalent grafting of vinyl monomers on the cellulose backbone is inconceivable. [ABSTRACT FROM AUTHOR]

In the present investigation, Raman spectroscopy is used to study the modifications caused by Compton electrons, originated by gamma quanta of 60 Co on the crystalline structure of graphite. The samples were irradiated in a dose range between 40 and 160 kGy. The analysis of the Raman spectra allowed to corroborate the electrons that occur at these radiation doses are able of causing appreciable modifications in the graphite structure. These modifications have a complex dependence of radiation dose due to the concurrence of the "radiational damage" and "radiational annealing" processes. The analysis of the fine structure of the Raman 2D band shows that the effect of the Compton electrons goes beyond the production of vacancy-interstitial pairs, since it leads to the modification of the disposition and stacking order of the plans in the structure of graphite. [ABSTRACT FROM AUTHOR]

Physics education has been identified as one of the public sectors that are mostly influenced by technological developments. This paper adopted the quasi-experimental pre- and post-test design to assess the effects of multimedia-aided technologies (MAT) on undergraduate students' performance in quantum physics (QP) at the University of Rwanda College of Education (UR-CE). The researcher used purposive sampling to get 385 undergraduate students. Participants were randomly allocated into experimental (group A) and control (group B) groups. Group A (187 students) students were taught selected topics of quantum physics (blackbody radiation, photoelectric effect, Compton effect, wave aspects of particles, De Broglie's hypothesis, diffraction, interference and double-slit experiment, model of the atom, uncertainty relations, wave function, and Schrodinger equations) for 6 weeks using multimedia-aided technologies and engage, predict, observe, and explain (EPOE) method, whereas group B (187 students) was taught same topics during the same period with a lecture method. The results of ANCOVA revealed that the group's performance was the same (p >.05) before learning with no effect size (.000), while they diverged after learning with different teaching interventions. The significance was very high and statistically different (p <.001) with a large effect size (>.5). This implies that students taught with multimedia-aided technologies (experimental group) outperformed those students taught with lecture teaching methods (control group). Thus, the study recommends that educators should adapt teaching using MAT and EPOE strategy not only in QP but also in other domains of physics to improve active engagement, understanding levels, and academic achievement. [ABSTRACT FROM AUTHOR]

The article presents the results of the numerical simulation of the signal formation process of the background wires of self-powered neutron detectors (SPND) under the action of gamma radiation in the VVER-1000 core using MCNP code. The validation of the MCNP model was carried out on the results of experimental determination of the current of the background wires of the SPND, obtained at three different power units with VVER-1000 during the fuel campaign. The article also proposes a new gamma-ray method for determining the thermal power of the VVER-1000 reactor (TPR) based on the signals from the background wires of the SPND. TPR is an important safety parameter of VVER-1000, therefore, increasing the accuracy of determining TPR with the introduction of an additional gamma method for its determination is an urgent task, given the plans to increase the TPR of VVER-1000. The results of the experimental determination of the VVER-1000 TPR by the traditional neutron method based on the SPND signals are presented, and problematic issues regarding the error in determining the TPR by the neutron method are pointed out. The article presents the results of modeling to study the influence of the main factors affecting the change in the proportionality coefficient Kgm between the actual TPR and the TPR determined by the gamma method. To improve the accuracy of determining the TPR by the gamma method, a correction model for Kgm is proposed, which takes into account the effect of nuclear fuel burnup on the change in the signal of the background wires of the SPND. Taking into account that the signal of the background wires of the SPND is inertialess with respect to the change in the neutron power of the reactor, the introduction of the method for determining the TPR by the gamma method is promising for the implementation of an additional alternative channel for generating an emergency protection signal in terms of both power and the period of the reactor.

We theoretically study the Breit–Wheeler resonant process modified by a strong electromagnetic field represented as a plane monochromatic wave. The resonant kinematics of the process is studied in detail. It is shown that the energy of final particles (electron and positron) depends on two factors, the electron (positron) outgoing angle and the typical quantum parameters of the Compton effect and Breit–Wheeler process stimulated by the external field. The resonant differential cross section is obtained in the absence of the interference of reaction channels. It is shown that the resonant differential cross section can exceed the corresponding differential cross section of the Breit–Wheeler process in the absence of the external field by six orders of magnitude. [ABSTRACT FROM AUTHOR]

Sensitivity and detection limit of X‐ray detectors are crucial for security checks, medical diagnoses, and industrial inspections. In this study, it is reported that introducing some cations containing lone‐pair electrons is beneficial for enhancing the Compton scattering effect and thus improving X‐ray detection performance. As an example, SnTe3O8 is selected and grown as a novel high‐temperature X‐ray detection crystal. Because of the high resistivity of 2 × 1014 Ω cm and high mobility lifetime product of 3.22 × 10−4 cm2 V−1, SnTe3O8 X‐ray detector exhibits a high sensitivity of 436 µC Gyair−1 cm−2 under 120 keV hard X‐ray, a low dark current drift of 2.44 × 10−9 nA cm−1 s−1 V−1 and a record low detection limit of 8.19 nGyair s−1 among all oxide X‐ray detectors. Furthermore, the high‐temperature sensitivity of SnTe3O8 X‐ray detector is enhanced to 617 µC Gyair−1 cm−2 at 175 °C, which is ≈31 times larger than that of the commercial α‐Se. The high thermal stability and stable high‐temperature sensitivity of SnTe3O8 single crystal X‐ray detectors have potential applications in high‐temperature environments. The results not only provide an excellent high‐temperature X‐ray detection crystal but also propose an effective method to explore X‐ray detector materials with excellent performances. [ABSTRACT FROM AUTHOR]

The article presents a theoretical study of Oleinik resonances in the process of scattering a gamma quantum by an ultrarelativistic electron in the field of a strong electromagnetic wave with intensities up to 1027Wcm−2. The resonant kinematics for three possible resonant reaction channels in a strong external field have been studied in detail. It is shown that under resonant conditions, the scattering channels of the reaction effectively split into two first-order processes according to the fine structure constant, such as the external field-stimulated Compton effect. The annihilation channel of the reaction effectively decays into direct and reverse the external field-stimulated Breit–Wheeler processes. In the absence of interference from the reaction channels, a resonant differential cross-section was obtained in a strong external electromagnetic field. The cases when the energy of the initial electrons significantly exceeds the energy of the initial gamma quanta have been studied. At the same time, all particles (initial and final) fly in a narrow cone away from the direction of wave propagation. The conditions under which the energy of ultrarelativistic initial electrons is converted into the energy of a finite gamma quantum are studied. It is shown that the resonant differential cross-section of such a process significantly (by several orders of magnitude) exceeds the corresponding nonresonant cross-section. This theoretical study predicts a number of new physical effects that may explain the high-energy fluxes of gamma quanta produced near neutron stars and magnetars.

The process of Compton scattering by a free electron with subsequent reemission of one or two photons is considered in the assumption of finite interaction time. The corresponding cross sections are obtained in the framework of relativistic quantum electrodynamics using a modified form of fermion propagator with complex transmitted momentum. It is shown that finite time effects can be observable at sufficiently low energies of scattered photons. The proposed method also regularizes arising infrared divergence in the cross section of the double Compton effect. Possible experimental verification of considered theoretical approach is discussed. [ABSTRACT FROM AUTHOR]

Indeed, Compton's setup contained a Bragg spectrometer allowing for monochromatic, bright X-ray beams. The incident (i.e., cosmic) ray is first Compton scattered in the low-Z scintillator and then absorbed in the higher-Z NaI(Tl) array. This year is the 100th anniversary of the discovery of the Compton effect, marked by A. H. Compton's 1923 I Physical Review i article [[1]]. The various applications of the Compton effect and its "derivatives" (e.g., inverse Compton scattering) impact many areas of physics and chemistry. [Extracted from the article]

The article presents the results of the numerical simulation of the signal formation process of the background wires of self-powered neutron detectors (SPND) under the action of gamma radiation in the VVER-1000 core using MCNP code. The validation of the MCNP model was carried out on the results of experimental determination of the current of the background wires of the SPND, obtained at three different power units with VVER-1000 during the fuel campaign. The article also proposes a new gamma-ray method for determining the thermal power of the VVER-1000 reactor (TPR) based on the signals from the background wires of the SPND. TPR is an important safety parameter of VVER-1000, therefore, increasing the accuracy of determining TPR with the introduction of an additional gamma method for its determination is an urgent task, given the plans to increase the TPR of VVER-1000. The results of the experimental determination of the VVER-1000 TPR by the traditional neutron method based on the SPND signals are presented, and problematic issues regarding the error in determining the TPR by the neutron method are pointed out. The article presents the results of modeling to study the influence of the main factors affecting the change in the proportionality coefficient Kgm between the actual TPR and the TPR determined by the gamma method. To improve the accuracy of determining the TPR by the gamma method, a correction model for Kgm is proposed, which takes into account the effect of nuclear fuel burnup on the change in the signal of the background wires of the SPND. Taking into account that the signal of the background wires of the SPND is inertialess with respect to the change in the neutron power of the reactor, the introduction of the method for determining the TPR by the gamma method is promising for the implementation of an additional alternative channel for generating an emergency protection signal in terms of both power and the period of the reactor. [ABSTRACT FROM AUTHOR]

While physics has a rather ahistoric teaching tradition, it is common to include at least anecdotal reference to historical events and actors. These brief remarks on the history are typically distorted. I take issue with the textbook narrative of the historical development of early quantum theory and rectify some of the more severe misrepresentations. This seems to be all the more important, since the history of physics is commonly (and rightly) regarded as a means to foster scientific literacy and a more appropriate understanding of the nature of science (NoS).

Commercial micro X-ray fluorescence (μXRF) systems often employ a tilted convergent beam, which can cause a misalignment between X-ray cartography and the corresponding visible images. This misalignment is typically considered a disadvantage, as it hinders the accurate spatial correlation of elemental information. However, this apparent drawback can be exploited to facilitate X-ray stereoscopy.To demonstrate the use of unmodified commercial μXRF equipment to estimate the 3D configurations of metals and voids within a low-atomic-weight matrix, specifically polymethyl methacrylate, and to explore the implications for enhancing μXRF mapping techniques. This approach could have applications in materials science, archaeology, and other fields requiring non-destructive 3D chemical mapping.Using unmodified commercial μXRF equipment, we leveraged both XRF and Compton scattering effects to quantitatively reconstruct the size, position, and depth of embedded tungsten, copper, and silver objects. The study specifically examines how beam divergence affects the acutance of objects located deeper within the sample.Our findings indicate a depth estimation bias ranging from 4% to 15% for depths between 24 mm, and a size estimation bias below 3.2%. These results validate the methodology and highlight the robustness of our approach under typical operational settings, suggesting that the technique could be applied to a wide range of samples with minimal modifications to existing μXRF systems.The study confirms that the inclination-induced misalignment in μXRF systems can be harnessed to enhance three-dimensional imaging capabilities. Our work establishes a foundation for advancing current μXRF mapping techniques and interpretation strategies, potentially broadening the applications of μXRF in various scientific and industrial fields. [ABSTRACT FROM AUTHOR]

Due to the influence of the Compton effect and the relatively close gamma energy emitted during certain nuclide decays, gamma-ray spectrum analysis often faces challenges, such as a high count of Compton scattering continuum and overlapping peaks, which leading to some errors in energy spectrum analysis and low nuclide identification rates. This study proposes a spectrum analysis technique that uses Gaussian convolution to effectively eliminate background counts induced by Compton scattering. To minimize calculation errors in variance, the variance error is decreased from 2.98% to 0.84% through the utilization of a binary method for adjusting the transformation scale. Simulation results show that the average relative error of peak area calculations is less than 10.78%, and in the range of signal to noise ratio (SNR) greater than 22.5 dB, the differences between the standard peak center position and the peak center position measured by the Gaussian convolution method are less than 0.049%. The measured spectrum experiments were also carried out to confirm that the average relative error of peak area calculation is around 7.63%, and the relative error between the Gaussian convolution method and Gamma Vision peak-seeking result is around 0.18%. These results demonstrate that this method can effectively eliminate the Compton scattering background counts in the gamma spectrum, obtain the peak position and peak area of the full energy peak, and facilitate the accurate identification of the weak peak in the gamma spectrum. • A new method is proposed to eliminate Compton scattering background counts. • The peak center calculation errors are less than 0.049% with different noise levels. • The average error in peak area calculation is 10.78% with different noise levels. • Accurate calculation of peak parameters in noble gas gamma energy spectra. [ABSTRACT FROM AUTHOR]

Background: Several animal teeth have been used in laboratory tests with the assumption that they exhibit similarities with human teeth. Although various studies have been carried out to compare animal to human teeth, no conclusive studies have yet warranted the use of animal teeth in laboratory tests. The primary criterion for the selection of teeth of different species is their structural and physicochemical properties. Swine teeth are also used as substitutes for human teeth in studies of adhesion and amelogenesis, because they are more similar to human teeth than the teeth of other mammals in relation to shape, size, morphology and period of development. In addition, some enamel proteins used for periodontal therapy are extracted from swine tooth germs because it is considered that composition of swine enamel is similar to human enamel. On the other hand, swine teeth are higher and more complex in shape than human teeth, having a greater number of cusps and irregularities. Studies showed that swine teeth are less resistant to fracture under compressive forces in comparison with human teeth, which is probably due to their thinner enamel. The present work stands out because of its originality, since when doing a bibliographic search; we have found just a few references about pig species, where all the anatomical references, morphology, physiology, classification, descriptive elements and work model for teeth in pig are described in such a detailed way. Materials and Methods: A detailed search has been done on Google scholar and PubMed for identification of research papers related to swine teeth and human odontology. The important research works found during the manual search were also gathered in this review. During search, some keywords such as "odontology" or "human" or "radiodensity" or "swine teeth" or "dentin and enamel" or "imaging" were used. Results: The photoelectric effect is considered to be an example of the absorption phenomena. The Compton effect is an example of the scattering phenomena and approximately 62% of the photons undergo Compton interactions. Irrespective of the type of X-ray-to-matter interactions, it is always directly proportional to either the atomic number of the absorber or to its electric density. Thus, depending on the atomic composition of the matter, the radiodensity of a radiographic image will be differently influenced. At this point, literature is too contradictory. Some authors state that all mammalian teeth are essentially similar but the trace element concentration in the enamel of human and swine teeth are similar to each other. The form of the pulp cavity resembled the shape of the tooth as in human teeth. Conclusion: Based on the findings of selected articles in this review, inconsistent data exist regarding that swine teeth can be considered appropriate substitute for human teeth, in the reviewed fields of dental research with many of the characteristics of the ideal animal in dental research, such as: similar growth rate, physiology and suitable size of teeth and mandible to allow dental operations and growth measurements. [ABSTRACT FROM AUTHOR]

Photons (Solar) are the main source of energy available on Earth and provide hope of clean energy in the future, photon energy has particle characteristics, and there is an inevitable connection between the wave behavior and the particle behavior of light, in-depth understanding and exploration are required. Based on the hypothesis of the strong interaction between electrons and protons to generate photons, the energy and behaviors of photons are discussed herein. By analyzing and calculating the photon speed, the negative photon speed was found to be in excellent agreement with the existing light speed constant. The Compton effect wavelength shift was analyzed and deduced considering the interaction of positive photons and atoms, and new conclusions are drawn, proposing the reason why X-rays are positive photons. Based on existing data, the observed estimation value of the negative photon velocity shift is 0.0295 ppm. From the interaction of the spin-charged particles, the relationship between the photon wavelength and its magnetic moment was calculated. In addition, we analyzed and calculated the characteristics of photon orbits, inferred the mechanism of atomic luminescence, and qualitatively explained the phenomenon of blackbody radiation. Based on the effect of charged spin photons and the electromagnetic potential field, we explain the reason for the simultaneous existence of reflection and refraction. The relationship between the incident angle and the reflectivity was analyzed, and refractive index formulas were derived to reasonably explain the characteristics of the X-ray refractive index. As a result, edge diffraction is considered a special case of refraction. By analyzing the fluctuation of the potential field inside the atom, the diffraction phenomenon of charged particles is described, and a particle explanation of the phenomenon of light waves and beat frequencies interference is provided. It is believed that the physical model of photon charging conforms to the existing physical laws. Photon energy is kinetic energy and is derived from the potential energy of electrons or protons.

This work is based on the following three premises: (1) Equality c = u with u = (-2U)1/2 as the total escape speed (from all the masses in the universe) and U the total gravitational potential; given a value of the universe mass, as shared by many physicists, u tends to c, hence constant on Earth. Moreover, the above equality implies the massiveness of light, which regards the second premise: (2) Structure of light: Longitudinal/sinusoidal particles, photons, moving along rays, having parameters k (their length) and frequency v (their number, of the same ray, flowing in a time unit); now, if photons and electron should have, at their impact, opposite direction, a circling electron could fall into its nucleus, hence the third premise. (3) A structure of the electron where its charge is not uniformly distributed, but it can be considered as a point particle fixed on the electron surface, facing the atom nucleus during the electron orbits; the electron charge corresponds to the photons-electron impact point, where photons are absorbed and released. Due to these structures, the photons-electron impacts will force the involved electron to move, with a radial velocity w, toward wider orbits. On these bases, and according to the classical mechanics laws, we found, but not limited to, these results: The measured speed of light, constant on Earth because of the equality #1, turns out to be also invariant whatever the relative motion observersource (of light) is: In short, during the interaction photons-electron, due to both the electron radial velocity and its Doppler effect, if the photons frequency decreases, then their length will increase (and vice versa) always inducing the invariant c. [The equality c = u has a cosmological reason: If c > u, all the visible masses, following the photons mass moving toward the infinity, would be dispersed from each other; if c < u all masses would collapse, while, for c = u, the photons mass (as well as neutrinos mass, as shown) will ensure an endless balance between dispersion and collapse.] The gravitational redshift and the claimed time dilation depend, like c, on the variation of the total potential. On H atom, the number of the electron circular orbits turns out to be n = 1, 2...137; the electron orbital speed along its ground-state (g-s) orbit becomes v1 = c/137, while the electron charge g-s orbital speed is vo = ac with a being the fine-structure constant. As for the claimed fall of circling electrons into their nucleus due to their supposed photons emission, we found that the circling electrons are emitting the previously absorbed photons only during the spiral path from higher toward lower orbits; this emission avoids their fall. Then we show that the compensation velocity (to restore the resonance source-detector located at different heights) has opposite direction with respect to the one predicted by relativity. [ABSTRACT FROM AUTHOR]

We theoretically investigated the sub-luminal and super-luminal light propagation by introducing compton scattering and Kerr non-linear effects to a four level atomic system. Slow light propagation is observed at a group index of 3918 in the transparency region. The slow light propagation is tuned to fast light propagation at group index 0.2, using compton scattering angle of φ = π / 6 . The surperluminality is further enhanced with compton scattering angle at the resonance frequency. Under the Kerr nonlinearity, the slow light propagation at a group index of 3918 is enhanced to fast light propagation at group index of 2 × 10 6 at the resonance frequency. The group index is reduced to 6.56281 × 10 - 5 in the presence of both Kerr non-linearity and compton scattering. In the presence of compton scattering, the Phase shift at π / 2 without Kerr nonlinearity is 7 × 10 - 8 radian and with Kerr nonlinearity its value is 1.7 × 10 - 9 radian at resonance frequency. This demonstrate that introducing Kerr effect and compton scattering lead to significant modifications in the phase shift. [ABSTRACT FROM AUTHOR]

The article presents a study which developed a framework to describe the nonperturbative interaction of a charged particle with driving fields of an arbitrary quantum light state. Topics discussed include nonperturbative interaction of matter with arbitrary light states in quantum electrodynamics (QED), the emission power spectrum of Compton scattering driven by arbitrary light states, and spectral broadening and higher harmonics induced by photon statistics.

This work investigates the cumulative dose 60Co gamma ( $\gamma$ ) – ray irradiation effects on enhancement mode HEMT devices inheriting 3D – Electron and Hole Gases for dosimeter applications. The devices are irradiated through a 60Co source and demonstrate the enhancement in the drain current metrics. To elucidate, the said devices were irradiated through different mechanisms and the Compton effect was investigated through contour plots via TCAD simulations. The degradation of Schottky Gate contact and insulator charging affects the 2D – Hole Gas at the GaN cap and thereby affects the bottleneck at the 3DEG sheet. This significantly affects the OFF – state leakage components of the said device and can therefore be exploited for potential use in sensing and dosimeter applications. The leakage components can be exploited further to improve the linearity of the dosimeter by considering different grading profiles of the AlGaN layer. In this regard, a workflow for optimizing the sensitivity and linearity of the dosimeter through different graded profiles is also presented. Amongst all, gaussian graded profiles have been identified as the best – case scenario considering the sensitivity and exhibiting a linear operation.

The article discusses a study by Baubeta et al. on gadolinium k-edge imaging in photon-counting CT scanners. The authors argue that the conclusion that gadolinium is not a clinically useful contrast agent for PCCT is unfounded due to technical flaws in the study design and analysis. They suggest that the use of virtual monoenergetic images (VMI) is not suitable for k-edge imaging and recommend more sophisticated multi-material decomposition techniques for future studies. The article emphasizes the importance of a proper theoretical framework and experimental design in advancing k-edge imaging technology in clinical applications. [Extracted from the article]

In a microscopic model of the photoelectric effect, it becomes clear that the conservation of energy is exclusively determined by Doppler shift processes, i.e., the whole energy of the photon vanishes by means of Doppler redshifts. Accordingly, if a photon is generated, the energy is won by Doppler blueshifts. This is supposed to be valid for all processes with energy conservation. An experiment is carried out to make this Doppler energy flow visible by means of interactions with probes. The result of this experiment is that a weak force is measurable in the vicinity of processes with energy conservation. With the aid of a twisted rubber-driven low-power device (P˜=10W\tilde{P}=10\hspace{.5em}\text{W}), periodic accelerations and decelerations of about 10−6 m/s2 are measurable. In the close vicinity of the device, accelerations with values up to 10−3 m/s2 can be concluded. The consequences that result from this force are discussed.

Overcoming radio-resistance and enhance radio-sensitivity to obtain desired therapeutic outcome plays an important role in treating cancer. Here we constructed a versatile enzyme-like nano-radiosensitizer MDP. MDP is composed of MnCO decorated and Ru-based nanozyme with triphenylphosphine (TPP) group coordinated on the surface. Due to the mitochondria-targeting ability of TPP and enhanced permeability and retention effect (EPR) effect of MDP, MDP accumulated in the mitochondria of tumor cells. Therefore, quantities of reactive oxygen species were produced via multiple enzyme-like properties including peroxidase (POD) and catalase (CAT) in a tumor microenvironment mimicking status. In additional, more energy of radiation ionizing was deposed in tumor site via Compton effect and secondary electron scattering by Ru element. Impressively, it was disclosed that the nanozyme can act as a cGAS-STING agonist to provoke immune response of the system, which hereby further elevated this combined therapy. Collectively, we fabricated a novel nanozyme with POD and CAT mimicking properties for the combination therapy of catalytical therapy, radiotherapy as well as immune therapy to eliminate cancer. • A dual catalytic of catalase (CAT)-like and peroxidase (POD)-like nanozyme termed MDP was synthesized. • With triphenylphosphine (TPP) decoration, MDP demonstrated outstanding mitochondrial targeting ability. • MDP showed potential in radiosensitization by modulation of immunosuppressive tumor microenvironment through activating cGAS-STING pathway. [ABSTRACT FROM AUTHOR]

Compton backscatter imaging (CBI) is a non-destructive testing (NDT) technique with the Compton effect. In CBI, the radiation source and detector are positioned on the same side of the object, which means that the imaging is almost not limited by the size of the object. The characteristic of single-sided imaging gives CBI substantial potential for applications in specific scenarios. In field archaeology, CBI can rapidly acquire subsurface images with the millimeter-level resolution, effectively enhancing archaeological excavation efficiency while better protecting artifacts. Therefore, CBI offers substantial potential in archaeological excavation. To address the problem of severe noise in CBI, we employed a scintillation detector to receive backscattered X-rays. Transformers directly reconstruct multi-channel projections to swiftly and accurately obtain precise reconstruction images. Monte Carlo simulation experiments confirm this method's suitability for detecting a variety of common archaeological materials. Experimental results indicate that compared with count mode, multi-channel projections can effectively improve the reconstruction quality of CBI. Moreover, CBI can clearly image various materials of buried artifacts, proving the method's versatility and practical value in NDT field. • Rapid and accurate X-ray backscatter imaging employing data of scattered X-ray spectrum. • A large number of data for field archaeology in random scenarios are obtained through Monte Carlo simulation. • Implementing deep learning for attenuation correction and reconstruction for the first time. [ABSTRACT FROM AUTHOR]

Understanding the thermal properties and enhancing the performance of zirconium diboride (ZrB 2) under extreme conditions is crucial, especially given its role as a burnable absorber in nuclear fuel pellets and its potential applications in accident-tolerant fuels. This study explores the structural alterations of ZrB 2 crystals induced by gamma irradiation and subsequent thermal annealing. ZrB 2 crystals were exposed to absorption doses of 300 kGy, 1000 kGy, 1500 kGy, and 3000 kGy using a 60Co gamma source, followed by thermal treatment at 1173 K under vacuum conditions. Also, Monte Carlo simulations were utilized to analyze the energy deposition and distribution of gamma quanta within the material during irradiation, highlighting Compton effects up to 0.23 MeV. X-ray diffraction analysis elucidated the impact of gamma radiation on ZrB 2 crystal lattice parameters, space group, and volume expansion coefficient. Post-irradiation analysis revealed a maximum degree of amorphization and investigated mechanisms governing lattice parameter expansion. Thermal annealing at 1173 K significantly enhanced crystallinity, reducing amorphization to 0.2 % at an absorption dose of 3000 kGy and facilitating the restoration of the crystal's columnar structure. This comprehensive investigation provides insights into the intricate interplay between gamma irradiation, thermal processing, and resulting structural changes in ZrB 2 nanocrystals, essential for applications in radiation-exposed environments. • ZrB 2 exhibited a maximum amorphization of 1.2% at an absorption dose of 3000 kGy. • Thermal treatment at 1173 K reducing amorphization to 0.2% at 3000 kGy without inducing phase transitions or oxide formation. • At (101) diffraction peak revealed a threefold increase in crystalline regularity at 1173 K. [ABSTRACT FROM AUTHOR]

This paper focuses on additional inspections concerning the fermionic sector of the Standard Model Extension (SME). In this context, our main effort in this contribution is to investigate effects of Lorentz-symmetry violation (LSV) on the Klein Paradox, the Zitterbewegung and its phenomenology in connection to Condensed Matter Physics, Atomic Physics, and Astrophysics. Finally, we discuss a particular realization of LSV in the Dirac equation, considering an asymmetry between space and time due to a scale factor present in the linear momentum of the fermion, but which does not touch its time derivative. We go further and extend the implications of this asymmetry in the situation the scale factor becomes space–time dependent to compute its influence on the kinematics of the Compton effect with the extended dispersion relation for the fermion that scatters the photon. • Additional inspections concerning the fermionic sector of the SME. • Effects of LSV on the Klein Paradox, the Zitterbewegung and its phenomenology. • Dirac equation with a space and time asymmetry due to a scale factor in the momentum. • The implications of the Compton effect with a space-time dependent scale factor. [ABSTRACT FROM AUTHOR]

While physics has a rather ahistoric teaching tradition, it is common to include at least anecdotal reference to historical events and actors. These brief remarks on the history are typically distorted. I take issue with the textbook narrative of the historical development of early quantum theory and rectify some of the more severe misrepresentations. This seems to be all the more important, since the history of physics is commonly (and rightly) regarded as a means to foster scientific literacy and a more appropriate understanding of the nature of science (NoS). [ABSTRACT FROM AUTHOR]

Introduction: Photoelectric effect and X-ray scattering determine the attenuation coefficient of materials in diagnostic radiology. This manuscript presents an iterative gradient search method to separate the contributions to attenuation from these two independent sources. This issue assumes importance due to two reasons, including 1) Electron density determination of scanned materials and 2) correct dose calculation in diagnostic radiology. Material and Methods: A special water-filled phantom which was custom-built for simultaneous scanning of 12 samples was used in the current study. Attenuation coefficient equations were iteratively solved to calculate the contributions from x-ray scattering and photoelectric effects. Results: Data converged after five iterations (within 1%). Error in the attenuation coefficient was measured at ±3%. Conclusion: As evidenced by the obtained results, this method can be used to determine the Compton and photoelectric contributions with sufficient accuracy. Moreover, the inversion of Dual- Energy computed tomography (DECT) data for finding electron density and effective atomic number of materials also presents satisfactory results.