Gamma-ray Energy Research Articles

CaO-enhanced polyester for safety: experimental study on fabrication, characterization, and gamma-ray attenuation

Abstract The current work deals with studying the influence of cheap, widespread CaO on improving the γ ray-protection capacity of the lightweight, sealing polyester. Therefore, polyester composites were filled with different concentrations of CaO fillers. The fabricated CaO-reinforced polyester composites’ density ranged between 1.177 g/cm3 and 1.377 g/cm3, when CaO filler concentrations increased between 0 wt% and 60 wt%, respectively. Fabricated composites’ morphology and chemical composition, as well as CaO fillers’ grain size and distribution, were proved using SEM and EDX spectroscopy. Additionally, the influence of CaO fillers on the gamma-ray shielding properties of the fabricated composites was evaluated using the Monte Carlo simulation and confirmed using the experimental measurements. The recorded results show an enhancement in the synthesized composites’ linear attenuation coefficient from 0.091 cm−1 to 0.106 cm−1 at a gamma ray energy of 0.662 MeV. Moreover, the excess in CaO concentration from 0 wt% and 60 wt% reduces the fabricated composites’ half-value thickness values from 7.64 cm to 6.51 cm, respectively.

Energy spectra of the first TGE observed on Zugspitze by the SEVAN light detector compared with the energetic TGE observed on Aragats

The energy spectra of Thunderstorm ground enhancement (TGE) electrons and gamma rays are the key evidence for proving the origin of enhanced particle fluxes from thunderclouds. Till now, the electron energy spectrum was measured only by the Aragats large scintillation spectrometer ASNT. We changed the electronics board of the SEVAN detector installed at the Umwelt-Forschungs-Station (UFS, Schneefernerhaus, 2650 m asl) to allow these vital measurements near the top of the Zugspitze. The new electronics of the SEVAN detector, supplied with logarithmic ADC, for the energy release measurements up to 50 MeV (the thickness of the spectrometric scintillator is 25 cm). Thus, by measuring energy releases well above 3 MeV, we unambiguously separate Radon progeny gamma radiation from the electrons and gamma-ray relativistic runaway avalanches. Using the different energy release histograms allows for separating charged and neutral particles, enabling the disentangling of electron and gamma-ray energy spectra. On May 23, 2023, the first TGE was registered on Zugspitze by the SEVAN detector. The gamma-ray flux enhancement was 44%, corresponding to the observed count rate peak enhancement of 44σ. The gamma-ray energy spectrum was recovered, maximum energy is 60 MeV. On the same day, a large TGE was observed on Aragats. The TGE maximum flux overpasses the fair-weather flux by 207%, equivalent to a 1-minute peak significance of 400σ. Maximum energy of electrons is 50 MeV, gamma rays – 45 MeV. In this context, we will explore and explain the new capabilities of the SEVAN detector installed on Zugspitze and the rearranged similar detector on Aragats. We also present and compare electron and gamma-ray energy spectra from Aragats TGE and gamma-ray energy spectrum from Zugspitze.

A comparative study on the scintillation characteristics of Gd2SiO5:Ce and Lu1.2Gd0.8SiO5:Ce scintillators

In the present day, inorganic scintillators have been developed to detect high-energy photons such as x-rays and γ-rays. They have been applied in many works, such as astronomy, materials inspection, high energy physics, industrial application, and natural resources exploration. Especially in the medical field, they are used as radiation detectors in diagnostic equipment such as PET scanner, x-ray CT scanner, SPECT scanner, etc. This research studied the scintillation characteristics of Ce:GSO and Ce:LGSO single crystals. We found that at 662 keV gamma-ray energy, Ce:LGSO crystal has about 2.3 times more light yield than Ce:GSO crystal, but the energy resolution of both crystals is not different. For the degree of non-proportionality of both crystals, Ce:LGSO scintillator shows 0.08, which is better than the 0.19 obtained from Ce:GSO scintillator. This work also discusses the two scintillators’ peak-to-total ratio, loss parameter, and intrinsic light yield.

An ultrahigh-energy [formula omitted]-ray bubble powered by a super PeVatron

We report the detection of a γ-ray bubble spanning at least 100deg2 in ultra-high energy (UHE) up to a few PeV in the direction of the star-forming region Cygnus X, implying the presence super PeVatron(s) accelerating protons to at least 10 PeV. A log-parabola form with the photon index Γ(E)=(2.71±0.02)+(0.11±0.02)×log10(E/10TeV) is found fitting the gamma-ray energy spectrum of the bubble well. UHE sources, “hot spots” correlated with very massive molecular clouds, and a quasi-spherical amorphous γ-ray emitter with a sharp central brightening are observed in the bubble. In the core of ∼0.5°, spatially associating with a region containing massive OB association (Cygnus OB2) and a microquasar (Cygnus X-3), as well as previously reported multi-TeV sources, an enhanced concentration of UHE γ-rays is observed with 2 photons at energies above 1 PeV. The general feature of the bubble, the morphology, and the energy spectrum, are reasonably reproduced by the assumption of a particle accelerator in the core, continuously injecting protons into the ambient medium.

A comprehensive evaluation of Mg-Ni based alloys radiation shielding features for nuclear protection applications

The current study aims to study the impacts of the substitution of magnesium with nickel concentrations on physical and γ-ray shielding capacity of magnesium alloys. The density of the magnesium alloys under study is varied from 3.677 g/cm3 to 5.652 g/cm3, with raising the nickel content from 26.7 wt% to 54.8 wt% and reducing the magnesium concentration from 72.6 wt% to 44.2 wt%, respectively. Additionally, the examination of the γ-ray shielding capacity using the Monte Carlo simulation code shows that the substitution of magnesium by nickel content in the magnesium alloys was associated with an enhancement in the γ-ray shielding capacity, where the linear attenuation coefficient for the studied alloys was enhanced by 53.22 %, 52.45 %, and 52.52 % at γ-ray energies of 0.662 MeV, 1.252 MeV, and 1.408 MeV, respectively, with raising the nickel concentration from 26.7 wt% to 54.8 wt%. Simultaneously, the half-value thickness for magnesium alloys was reduced from 2.47 cm to 1.62 cm (at gamma ray energy of 0.662 MeV), from 3.39 cm to 2.22 cm (at gamma ray energy of 1.252 MeV), and from 3.60 cm to 2.36 cm (at gamma ray energy of 1.408 MeV), raising the nickel concentration from 26.7 wt% to 54.8 wt%, respectively. The study shows that the substitution of magnesium for nickel greatly enhanced the radiation shielding capacity of the magnesium alloys.

Tungsten and Titanium dioxide filled VMQ polymer composites-a new lead free & flexible gamma ray-shielding materials.

Flexible & lead-free gamma-ray-shielding composites were prepared using Vinyl Methyl Silicone (VMQ) matrix with Tungsten (W) and Titanium dioxide (TiO2) as fillers. The VMQ composites filled with 30Phr (parts per hundred rubber) TiO2 and 0-70Phr W were prepared by two-roll mill method. The dispersion of the filler particles in the composite matrix was analysed using Scanning Electron Microscope. Gamma ray shielding properties were studied in the energy range of 80 to 1170keV using NaI(Tl) scintillation spectrometer. The mass attenuation coefficient (μm) of the prepared composites was found to increase with increasing concentration of W. Mass attenuation coefficients of 30Phr W composites at gamma-ray energies of 356 and 1170keV were found to be 0.1444 and 0.0644cm2g-1, while those of 50Phr W composite were 0.1396 and 0.0707cm2g-1, respectively. The half value layer values of all the samples were found to decrease with increase in tungsten concentration. To appreciate the shielding ability of the prepared composites, comparison was made with the metal lead. The results show that addition of W into VMQ enhances the attenuation, whereas tensile strength and elongation at break reduces. The Shore A hardness of the W/TiO2/VMQ composites had a maximum value of 71 and the composites also prove to possess good thermal stability. Hence, the present study shows that the VMQ based W-TiO2 rubber composites serve to shield gamma radiations in medical applications and are considered as environmental friendly.

Gamma Ray Spectrum by Software Methods for Radioactive Waste

The requirements of NTD (Neglected Tropical Diseases) and technological regulations for the operation of NPP (Nuclear Power Plant) power units (NP-001-97 (OPB-88/97), NP-082-07) define the requirements for monitoring the specific activity of iodine-131 (the amount of iodine) in the NPP primary circuit coolants. The advantages of laboratory control include accuracy of measurement and the radionuclide composition of the primary coolant, measured using high-precision laboratory equipment. Instrumental spectra were obtained for the detection units BDKG-205m with various options for the placement of waste in a container, their composition, mass of waste, average density, and various activity levels of waste. The basic idea behind gamma-ray spectroscopy is to detect and analyze the energy of incident gamma rays. Gamma rays of varying energy and intensity are emitted from radioactive sources. The gamma-ray energy spectrum is produced when gamma rays are detected and examined using a spectroscopy instrument. The initial stage in gamma-ray spectroscopy is to detect gamma rays using a suitable detector. The detector captures and measures the energy of incoming gamma rays. Scintillation detectors, semiconductor detectors, and gas-filled detectors are among the detectors used in gamma-ray spectroscopy. The incoming gamma-ray energy is converted into electrical signals that can be processed and studied by these detectors. The spectroscopic system measures and records the energy of gamma rays when they are detected. The derived energy spectrum depicts the intensity distribution of gamma rays as a function of energy. The spectrum is a visual representation of the different energy levels found in gamma-ray emission.

Evaluation of full-energy-peak efficiencies for a LaBr3:Ce scintillator through a Virtual Point Detector approach

The aim of this work is to investigate, in a wide range of gamma-ray energies, the validity of the “Virtual Point Detector” (VPD) approach to evaluate Full-Energy-Peak Efficiency (FEPE) values for a Cerium-doped Lanthanum Bromide scintillator (LaBr3:Ce). With VPD approximation, the detector is assumed equivalent to a virtual point inside the crystal where all the interactions can be considered to occur. The distance of VPD from detector cap is evaluated through experimental point source measurements. The knowledge of the trend of VPD depth as a function of gamma radiation energy allows the evaluation of FEPE values starting from an experimental reference value.The validation of the procedure has been performed by applying the VPD approach to measurement geometries already characterized such as a disk source, an Havar foil irradiated inside a target of a medical cyclotron, and a parallelepided sample geometry, an atmospheric particulate paper filter reduced to 6 cm × 6 cm × 0.7 cm dimensions. FEPE values determined by VPD approach lead to radionuclide activities very close to the ones already obtained with measurements carried out with other detectors.

Probing Orbital Parameters of Gamma-Ray Binaries with TeV Light Curves

Gamma-ray binaries are binary systems in which the energy flux peaks in the gamma-ray energy band. They harbor a compact object (a neutron star or a black hole) orbiting around a massive star, which provides a strong radiation field. It is believed that the gamma-ray emission from such objects can be strongly attenuated through the electron-positron pair production in gamma–gamma interactions. The importance of gamma–gamma absorption depends on the orbital phase and on the geometry of the system. In this work, we propose a method showing how the orbital parameters of gamma-ray binaries could be probed with TeV light curves that have imprinted features of gamma–gamma absorption.

Clay-based bricks’ rich illite mineral for gamma-ray shielding applications: An experimental evaluation of the effect of pressure rates on gamma-ray attenuation parameters

Abstract The objective of this study is to increase the natural clay mineral-based bricks’ ability to shield γ-rays without the use of external doping materials. Six brick samples were consequently developed at various pressure rates (PRs). The chemical composition and structure of the manufactured bricks are unaffected by the PR applied. The main constituents in the clay used to make bricks are illite and quartz minerals, according to an X-ray diffraction pattern. Additionally, scanning electron microscopy and energy dispersion X-rays have demonstrated the morphology and chemical composition of the used clay. Besides, the Mh-300A density meter shows an increase in the fabricated bricks’ density by increasing the PR, where the brick’s density increased by 32.92% by increasing the PR from 7.61 to 114.22 MPa, respectively. Also, the effects of the PR on the radiation shielding properties of the fabricated bricks were investigated using a NaI (Tl) detector. The data reveal that increasing the PR between 7.61 and 114.22 MPa improved the linear attenuation coefficient by 44.5, 23.8, 24.2, and 24.8%, respectively, for gamma-ray energies of 0.662, 1.173, 1.252, and 1.332 MeV. The capacity of fabricated bricks to shield against radiation increases as the linear attenuation coefficient increases. The lead’s equivalent thickness and half-value thickness of the fabricated clay-based bricks, on the other hand, decreased. As a result, the compacted natural clay brick, which is a lead-free material, provides a suitable alternative for gamma-ray shielding in radioactive locations.

Signal-background separation and energy reconstruction of gamma rays using pattern spectra and convolutional neural networks for the Small-Sized Telescopes of the Cherenkov Telescope Array

Imaging Atmospheric Cherenkov Telescopes (IACTs) detect very-high-energy gamma rays from ground level by capturing the Cherenkov light of the induced particle showers. Convolutional neural networks (CNNs) can be trained on IACT camera images of such events to differentiate the signal from the background and to reconstruct the energy of the initial gamma ray. Pattern spectra provide a 2-dimensional histogram of the sizes and shapes of features comprising an image and they can be used as an input for a CNN to significantly reduce the computational power required to train it. In this work, we generate pattern spectra from simulated gamma-ray and proton images to train a CNN for signal-background separation and energy reconstruction for the Small-Sized Telescopes (SSTs) of the Cherenkov Telescope Array (CTA). A comparison of our results with a CNN directly trained on CTA images shows that the pattern spectra-based analysis is about a factor of three less computationally expensive but not able to compete with the performance of an CTA image-based analysis. Thus, we conclude that the CTA images must be comprised of additional information not represented by the pattern spectra.

Radiation shielding properties of barite coated terry-cotton fabric

With the rapid development of technology, the radiation started to be used in many different fields and thus radiation protection becomes important. The use of radiation in basic science, industry, military purposes and medical applications has reached enormous dimensions. The protection of radiation, which has such a wide range of uses, has become inevitable. Dresses used by radiation workers are important against possible radiation damage. In this study, the linear attenuation coefficients have been measured to investigate the radiation shielding properties of terry-cotton fabric coated by barite in the rate of 0%, 40%, 50% and 60%. The measurements were performed using a NaI (Tl) detector at 511, 835 and 1275 keV gamma ray energies. It was found that the barite is an important materials and when it is used to coat fabric lead to improve radiation shielding properties.

Investigation of impact of soil texture, depth and gamma ray energy on the mass attenuation coefficient and determination of soil bulk density using Gamma-Ray Spectrometry

The determination of the gamma-ray attenuation coefficient is a critical parameter in the characterization of the extent and diffusion of gamma radiation within intricate materials, such as soil. Soils exhibit a complex and diverse composition, characterized by the presence of several phases, including minerals, gasses, organic matter, water, and metals. The study demonstrates the utilization of gamma-ray spectrometry to determine the mass attenuation coefficient and soil bulk density. The impact of incident gamma-ray energy, soil texture, and soil depth on the mass attenuation coefficient is also investigated. The experimental measurements were conducted utilizing a gamma spectrometer equipped with a 2″ × 2″ NaI(Tl) detector at gamma energies of 0.356, 0.662, and 1.332 MeV using 133Ba, 137Cs, and 60Co sources, respectively. The soil samples corresponding to two textures and three depths were collected from the research farms of the Department of Soil Science, Punjab Agricultural University, Ludhiana. The study revealed that the attenuation coefficient depends on the energy of incident radiation and the nature as well as the composition of the soil. The mass attenuation coefficient was observed to decrease rapidly with the increase in gamma radiation energy. Mass attenuation coefficient was found to be higher for sandy loam compared to sandy clay loam textured soil. Moreover, the attenuation coefficient was higher for the lower depths than the upper depth. The comparison between the experimental and predicted values of the mass attenuation coefficient, utilizing the XCOM-NIST framework, demonstrated a satisfactory level of concordance within a 10% margin for gamma energies measuring 0.356 and 0.662 MeV. However, the agreement was slightly less favorable, with discrepancies of less than 12% for sandy clay loam samples and less than 15% for sandy loam textured soil samples, when examining a higher gamma energy of 1.332 MeV. The measured value of mass attenuation coefficient was used to calculate soil bulk density, which agreed reasonably well with the values obtained with the conventional method. Specifically, the sandy clay loam samples displayed a range of 7–14% deviation, while the sandy loam textured soil samples exhibited a range of 14–23% deviation. The investigation can be expanded to ascertain significant soil properties, such as porosity and moisture content.

Development of an advanced velocity modulator for a portable Mössbauer spectrometer

Mössbauer spectroscopy is a nuclear spectroscopic technique that measures changes in energy on an atomic scale. In a Mössbauer spectrometer, a velocity modulator oscillates a radioactive source to vary the energy of gamma rays. Conventional velocity modulators use wires primarily as motion guides; however, the tension state of these wires may change over time. Membrane springs are thus used as an alternative to wires; however, they also present certain challenges related to their design, manufacturing, and assembly. Instead of wires or membrane springs, this study used a linear bearing with preloaded compression springs. The advantage of this mechanism is that permanent deformation or changes in spring stiffness minimally occur during spring assembly and operation. The developed velocity modulator is compact and light, making it ideal for portable applications. A digital controller is used to easily modify and customize control parameters and the supporting algorithm, which is not easily achieved with conventional analog controllers. Moreover, by applying a switching amplifier, low-power operation is also achieved. Feedforward control values are calculated by an iterative learning method that is robust to the control of repeated motion. Using finite element method simulations and experiments, the performance of the developed prototype was evaluated. The velocity signal demonstrated linearity with a correlation with a straight line of approximately 0.996 for a triangular velocity profile (satisfactory performance).

Dynamic co-irradiation techniques: A new method improving the electrical output of TENG by optimizing the charge capture capacity of polypropylene membrane

Triboelectric nanogenerator (TENG) is a new energy device which can convert mechanical energy into electric energy. Its development and application mainly depend on its output performance. Material improvement, structural optimization, surface modification and other methods have proved to be effective in improving the output performance of TENG. However, so far, there is no industrial technology that can both guarantee the high output performance of TENG and realize large-scale production. Here, we are the first to assemble Radiant polypropylene -TENG (RP-TENG), where the Radiant polypropylene friction material was obtained by the dynamic co-irradiation modification technology of polypropylene (PP). Through FT-IR, SEM and other analysis methods, the mechanism of TENG's electrical output improvement is explained from multiple perspectives. With the treatment under the irradiation dose of 28KGy, the current, charge, and voltage of the RP-TENG reaches up to 9.67 μA, 109.06 nC and 220 V, which is about 4.4 times, 2.5 times and 2.2 times respectively that of the TENG assembled by commercial PP. The reason for the improved performance of the RP-TENG is that the high energy of gamma rays can enhance the surface electron density of the material and change the electron transfer ability of the dielectric material. In addition, the grafted amide group makes the surface of the friction material more prone to electron loss. The homomorphic co-irradiation technology can confer better electrical properties on the friction layer, which provides a new means for enhancing the properties of polymer-based TENG.

Novel bricks based lightweight Vietnam's white clay minerals for gamma ray shielding purposes: An extensive experimental study

In the present work, a new brick series based on the Vietnamese white clay minerals from the Bat Trang was fabricated to be applied in the radiation protection applications during the decommissioning of the nuclear power reactors. The bricks were constructed under various pressure rates varied from 7.61 MPa to 114.22 MPa. The influence of pressure rate on the physical and γ-ray shielding properties were investigated in the study. The experimental measurement for the material's density using the MH-300A density meter showed an enhancement in the prepared bricks' density by 22.5 % with increasing the applied pressure rate while the bricks' porosity reduced by 31.2 % when the pressure rate increased from 7.61 MPa to 114.22 MPa. The increase in the fabricated bricks density and the reduction in their porosities enhances the bricks' linear attenuation coefficients as measured by the NaI (Tl) detector along the energy range extended from 0.662 MeV to 1.332 MeV. The linear attenuation coefficient increased by 13.8 %, 17.6 %, 17.0 %, and 17.1 % at gamma ray energies of 0.662 MeV, 1.173 MeV, 1.252 MeV, and 1.332 MeV, respectively. The enhancement in the linear attenuation coefficient increases the bricks' radiation protection efficiency by 10.22 %, 14.48 %, 14.09 %, and 14.26 % at gamma ray energies of 0.662 MeV, 1.173 MeV, 1.252 MeV, and 1.332 MeV, respectively.

Evaluation of effective dose for gamma-rays of terrestrial gamma-ray flashes in aviation: spectral- and atmosphere-effects

Terrestrial Gamma-ray Flashes (TGFs) are intense and fast gamma-ray emissions, energy up to 100 MeV, generated within the Earth's atmosphere at altitudes below 20 km. Satellite observations indicate the TGFs are not a rare phenomenon, being produced on average at one per thunderstorm, yielding a global production rate of ≈35 TGFs/min within a latitude band of ±38°. Furthermore, the TGFs may coincide with the flight altitudes for several commercial aircraft routes, typically within the 10−14 km range, and thus cause passengers/crews unexpected exposure to large fluxes of high-energy ionizing radiation, namely for distances of the order of km.Herein, we introduce a novel approach based on a simple analytic/numeric methodology to estimate the TGFs gamma-ray emissions effective doses based on the differential fluence of photons at aircraft altitude and tabulated effective dose conversion coefficients versus the photon energy. For the first time, we examine the effective dose dependence on TGF's gamma-ray energy spectrum models found in literature and the atmosphere mass thickness crossed by the gamma-rays. Additionally, since the real irradiation geometry of the whole body in aircraft might be a combination of the several idealized geometries used in radiation protection, we considered beyond the typical anteroposterior (AP), the posteroanterior (PA), and the rotational (ROT) geometries as representative irradiation geometries in exposure to TGF gamma-ray's emissions.We calculated the effective dose versus the distance between the TGF site and the aircraft altitude (12.5 km) within the 0.1−5.0 km range and atmosphere mass thickness within the 3.3−213 g cm−2 range. Additionally, we calculated the average effective dose per fluence versus the atmosphere mass thickness crossed by the gamma-rays. At a distance of 1 km (34 g cm−2) and for the typical exponential cut-off power-law model (α = 1, EC = 7.3 MeV), the effective dose was within the 0.18−0.19 mSv range, being the respective average effective dose per fluence within the 10.8−11.6 pSv cm2 range. Moreover, for the variant of the exponential cut-off power-law model (α = 1, EC = 7.3 MeV, Emin = 1 MeV), the effective dose was within the 0.42−0.46 mSv range, being the respective average effective dose per fluence at 34 g cm−2 within the 12.7−13.6 pSv cm2 range.Generally, the data obtained agree with the scarce data found in the literature for similar conditions, evidencing the effect of the parameterization of the TGFs gamma-rays energy models, which may result in a 2- to 10-fold effective dose escalation. For the typical exponential cut-off power-law model (α = 1, EC = 7.3 MeV), the data obtained for an aircraft that passes through the vicinity of one TGF, with a distance of 1 km, points to an increase of the aircraft crew and passengers' doses of few tenths mSv over the cosmic radiation dose of few tens μSv along a typical flight of 6 h duration, representing ≈20% and ≈1% of the ICRP-2007 annual reference levels for passengers (1 mSv) and aircraft crew (20 mSv), respectively. More, with a distance of 0.5 km, the effective dose value is comparable with the annual dose for the aircraft crew due to the cosmic radiation for a typical yearly flight time of 500 h, representing ≈130% and ≈7% of the ICRP-2007 annual reference levels for passengers and aircraft crew, respectively.

Effect of heavy-weight recycled materials on radiation shielding and properties of high-strength concrete with CEM III

This research aims to study the effect of replacing up to 100% of recycled coarse aggregates with heavyweight aggregates. In addition to the effect of adding heavyweight aggregate slag on the efficiency of shielding against radiation and on the mechanical physical properties and elevated temperature of heavyweight high-strength concrete (HWHSC). In this investigation, HWHSC mixtures incorporate lead slag (LS), copper slag (CS), and steel slag (SS) as coarse aggregate. Recycled heavyweight coarse aggregates are added to concrete mixtures at volume ratios of 0%, 25%, 50%, 75%, and 100%. Slump test, compressive strength, flexural strength, tensile strength, elastic modulus, and bulk density tests were carried out. Three different gamma-ray energies at 137Cs 662, 60Co 1173, and 60Co 1332 (keV) sources were used to evaluate the mass attenuation coefficient, linear attenuation coefficient, half and tenth-value layer, and mean free path. To evaluate the impact of elevated temperature on density, compressive strength, and radiation shielding properties, concrete mixtures were exposed to 22 °C, 300 °C, 500 °C, and 800 °C. Compared to basalt-based concrete, heavy-weight concrete (HWC) incorporating LS, CS, and SS coarse aggregate has a significantly higher density. The results show a good effect of recycled heavyweight coarse aggregates on fresh, mechanical, and radiation-shielding properties. The density of the developed high-strength concrete (HSC) mixes ranges between 2400 and 3370 kg/m3, and the increase in recycled heavyweight coarse aggregates replacement ratio up to 75% increased all mechanical characteristics of HWC mixtures. Using LS as a replacement of basalt by 75% resulted in the highest compressive strength, splitting tensile strength, flexural strength, and elastic modulus of 105.8 MPa, 14.2 MPa, 19.5 MPa, and 45.76 GPa, respectively. Compared to basalt, LS, CS, and SS eliminate the impact of elevated temperatures on HSHWC strength. The best radiation protection properties were achieved with the complete replacement of basalt by LS.

Non-proportionality of Light Yield of CeBr3 Scintillator

Cerium bromide (CeBr3) scintillation crystal were studied and analyzed from the photon and electron response measurements. For photon response measurements, the radioactive source has been used for the energy range of 0.356 MeV ≤ E ≤ 1.332 MeV. The 137Cs source irradiated with gamma ray energy at 0.662 MeV was used for the electron response measurement using Compton coincidence technique. The variable angles (θ) would generate the gamma energies corresponding to a scattering angle of 30° to 120°. The results of number of photoelectron (Nphe) show responds to linear trends for photon and electron response. The light yield shows increase with increasing the photon and electron energy. The results showed the non-proportionality of photon response and electron response demonstrated good proportional properties of all energy ranges and as the result, the crystal is a promising candidate for gamma or X-rays detection.

Calculation of radiation shielding parameters of YBa2Cu3O7 and Y3Ba5Cu8O18 superconductors for the energies from 122 to 1332 keV using EGS4 code

This Study aims to evaluate the radiation shielding efficiency of YBa2Cu3O7 and Y3Ba5Cu8O18 superconducting ceramics. In the current study, the radiation shielding efficiency of YBa2Cu3O7 and Y3Ba5Cu8O18 superconducting ceramics were calculated using the EGS4 code and discussed experimentally and theoretically by comparing with XCOM data. The mass attenuation coefficients (μ/ρ) for YBa2Cu3O7 and Y3Ba5Cu8O18 superconductors and their contents was investigated theoretically (EGS4 and WinXcom) and experimentally at gamma-ray energies from 122 to 1332 keV. The theoretical values have been computed in the energy range from 1 keV to 100 MeV using WinXcom program. Then, using the mass attenuation coefficients, it was determined some shielding parameters such as mean free path (MFP), half value layer (HVL), effective atomic number (Zeff), radiation protection efficiency (RPE) and gamma–ray kerma coefficients ((kγ). It has been seen that the theoretical and the empirical results were in agreement. The data and findings from this study can guide further research and development of shielding materials for gamma-ray and neutron shielding applications.