Sürdürülebilir Kalkınma Amaçları
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- MakaleYalnız künye2026Optimizing compton suppression systems: A parametric monte carlo study of NaI scintillator geometry
Kaya, Ali; Çelik, Necati; Kaya, Selim
Compton suppression systems are widely used to enhance gamma-ray spectral quality in applications such as nuclear safeguards and environmental radioactivity measurements. Although optimization of high-purity germanium (HPGe) detectors has been extensively reported, the geometric optimization of secondary sodium iodide [NaI(Tl)] scintillation detectors remains less studied. This work investigates the influence of annular and plug NaI(Tl) detector geometry—length, thickness, and radius—on Compton suppression performance using Monte Carlo simulations. Performance is evaluated in terms of the peak Compton suppression factor (CSFpeak) and total Compton suppression factor (CSFtotal). The results show that CSFpeak and CSFtotal increase with plug length (2–10.2 cm) and annular thickness (1–5.85 cm), with saturation observed beyond approximately 8–10 cm and 4–5 cm, respectively, due to reduced incremental photon absorption. The plug detector radius (3.72–5.1 cm) exhibits a nonlinear effect, with optimal performance achieved at 4.55–4.83 cm, beyond which gains are marginal (<5%). Suboptimal geometries (plug length <6 cm, annular thickness <3 cm, plug radius <4.28 cm) result in 20–60% lower suppression performance, increasing Compton continuum contributions in 662 keV spectra. The optimal configuration—plug length of 8–10 cm, plug radius of 4.55–4.83 cm, and annular thickness of 4–5 cm—achieves more than 90% of maximum CSFpeak and CSFtotal while maintaining a balance between performance and detector volume. These results provide quantitative design guidelines for optimizing NaI(Tl)-based Compton suppression systems for improved gamma-ray spectrometry performance.
- MakaleAçık Erişim2026La2O3 addition's effect on sodium-barium borosilicate glasses' radiation shielding capability: WinXCOM and EGS4 Monte Carlo analysis
Kaya, Selim
This study thoroughly investigated the impact of La2O₃ inclusion on the radiation shielding effectiveness of sodium-barium borosilicate glasses using EGS4 Monte Carlo simulations and WinXCOM computations. The gamma-ray shielding behavior of a set of glass samples was systematically investigated over a wide photon energy interval ranging from 50 to 2506 keV. The glass compositions were modified through the stepwise substitution of Na₂O with La₂O₃. Key radiation interaction and shielding metrics—including the mass attenuation coefficient (μ/ρ), half-value layer (HVL), mean free path (MFP), radiation protection efficiency (RPE), effective atomic number (Zeff), and kerma coefficients—were determined and comparatively evaluated. The results demonstrate that the progressive incorporation of La₂O₃ leads to a marked enhancement in radiation shielding performance, particularly within the low-and intermediate-photon energy ranges where photoelectric interactions prevail. The inclusion of La₂O₃ results in increased material density, μ/ρ, Zeff, and kerma values, while simultaneously reducing (HVL) and MFP.In conclusion, sodium-barium borosilicate glasses treated with La₂O₃ have better radiation attenuation capacities than their La₂O₃-free counterparts. These results validate the effectiveness of La₂O₃ substitution as an approach for customizing borosilicate glass systems for applications that need improved radiation shielding.
- MakaleYalnız künye2026Influence of holmium substitution on structural characteristics and radiation shielding parameters of YBCO (358) superconducting ceramics
Düzgün, İbrahim; Kaya, Selim; Gül, Osman
This study reports on the structural characterization, radiation shielding assessment, and magnetic-field response of holmium-substituted Y3-xHoxBa5Cu8O18+δ superconducting ceramics synthesized by the conventional solid-state reaction route. X-ray diffraction measurements on five compositions (x = 0, 0.75, 1.5, 2.25, 3) supported the formation of a dominant orthorhombic Y358-type matrix across the substitution range. Scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDS) revealed a progressive microstructural evolution with increasing Ho content, including SEM–BEC/EDS-detectable Ho-rich inclusions consistent with Ho2BaCuO5-type secondary particles at higher substitution levels. XCOM-based mass attenuation coefficients, half-value layer, mean free path, effective atomic number, radiation protection efficiency, gamma-ray kerma coefficients, and fast-neutron removal cross-sections were calculated for all five compositions over 50–2000 keV. EGS4 Monte Carlo simulations independently verified the XCOM results for three representative compositions (x = 0, 1.5, and 3). Ho-containing specimens exhibited a significant enhancement in photon absorption near 60 keV, associated with the increased photoelectric contribution of holmium in the vicinity of its K-absorption edge. Among the full five-composition series, the x = 2.25 specimen (ρ = 5.531 g cm−3) exhibited the best calculated shielding performance across the full energy range, owing to its highest bulk density combined with substantial Ho incorporation. The x = 1.5 specimen provided the most balanced calculated radiation-attenuation and hysteretic magnetic response among the three representative compositions examined by EGS4 and M–H measurements at 20 K, retaining approximately 93% of the reference M–H hysteresis area while full substitution reduces it by roughly 67%. These findings establish a multi-parametric reference dataset for Ho-substituted Y358 ceramics and demonstrate the promise of rare-earth-engineered superconducting ceramics as multifunctional materials in radiation-intensive environments.
- MakaleAçık Erişim2026Computational analysis of radiation shielding properties of BaO-modified magnesium borophosphate glasses based on WinXCOM and EGS4 Monte Carlo simulations
Düzgün, İbrahim; Çelik, Necati; Kaya, Selim
The increasing use of ionizing radiation in medical, industrial, and nuclear applications necessitates the development of advanced and environmentally friendly shielding materials. In this study, the gamma-ray shielding performance of BaO-modified magnesium borophosphate glasses with compositions xBaO–30MgO–10P2O5–(50−x)B2O3–10Na2O (x = 0–35 mol%) was theoretically investigated. The radiation attenuation properties were evaluated over a wide photon energy range (59.54–2000 keV) using the WinXCOM database and Monte Carlo simulations based on the EGS4 code. Key shielding parameters, including mass attenuation coefficient (μ/ρ), half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), radiation protection efficiency (RPE), and gamma-ray kerma coefficients, were determined. The results indicate that increasing BaO content enhances the attenuation capability of the glass system, particularly in the low and medium photon energy regions, due to increased density and effective atomic number. A good agreement between WinXCOM and EGS4 results confirms the reliability of the applied theoretical approaches. These findings suggest that BaO-modified magnesium borophosphate glasses are promising candidates for radiation shielding applications.
- MakaleYalnız künye2026Influence of Compton scattering and pair production in radiation shielding of Eu-doped Bi-2223 ceramics
Doğruer, Musa; Kaya, Selim
The gamma-ray attenuation behavior of europium (Eu)-doped Bi-2223 ceramic superconductors has been investigated in detail in this work in the photon energy range of 59.54 to 1332 keV. The WinXcom database was used to rigorously estimate the mass attenuation coefficients (μ/ρ), which are the main quantifiers of the probability of photon–matter interaction. Stochastic modeling based on the EGS4 Monte Carlo transport technique was then used to confirm the results. Key shielding metrics such as the mean free path (MFP), radiation protection efficiency (RPE), half-value layer (HVL), and gamma-ray kerma coefficients (kγ) are derived from these coefficients and offer information about the material’s inherent ability to dissipate or attenuate incident photon flux. Additionally, the effective atomic number (Zeff) was established to elucidate the role of compositional heterogeneity and atomic cross-section weighting in regulating photon absorption and scattering probabilities. Concurrently, the macroscopic fast neutron removal cross-sections (ΣR) were computed to measure the dual shielding capacity of the ceramics being studied against electromagnetic radiation and neutrons. The findings showed that although Eu doping led to a minor increase in the effective atomic number and μ/ρ values at lower photon energy, it also resulted in greater HVL and MFP values, particularly at higher energies. The total shielding performance decreases due to the decrease in bulk density, even though the addition of Eu results in better mass attenuation coefficients. The μ/ρ values of Eu-doped Bi-2223 ceramics exhibit high agreement and increase from 2.753 to 3.212 cm2 g−1 at 59.54 keV with increasing Eu content. These values were produced using EGS4 simulations and verified using WinXCOM in the 59.54–1332 keV energy range. This suggests that europium’s higher atomic number enhances photon absorption at lower energies. The study also demonstrates that the Eu-0 sample has the strongest neutron shielding capabilities and the highest radiation protection efficiency (RPE).
- MakaleYalnız künye2026Radiation shielding performance and microstructural characterization of Al–Cu-Sc/B4C nanocomposites
Şirin, Murat; Kaya, Selim; Temiz, Cengiz; Çağlar, Seyit
This study investigates the gamma-ray and fast-neutron shielding performance of Al–Cu–Sc/B4C nanocomposites containing 0–20 wt% boron carbide (B4C). The composites were produced using melt spinning, high-energy ball milling, and vacuum sintering techniques. Their structural and microstructural characteristics were examined by X-ray diffraction and scanning electron microscopy. Gamma-ray attenuation properties were measured experimentally at photon energies of 0.662, 1.173, and 1.333 MeV using a high-purity germanium detector. In addition, theoretical calculations were carried out in the 0.05–2.50 MeV energy range using Monte Carlo simulations together with the Phy-X/PSD calculation platform. Several radiation shielding parameters were evaluated, including the mass attenuation coefficient, half-value layer, mean free path, radiation protection efficiency, effective atomic number, and fast-neutron removal cross-section. The results show that the incorporation of B4C improves the fast-neutron shielding capability of the composites. The sample containing 20 wt% B4C exhibits an increase of approximately 32% in fast-neutron removal cross-section compared with the reference alloy. A slight reduction in gamma-ray attenuation is observed at low photon energy, whereas the shielding performance at medium and high energies remains nearly unchanged. These findings indicate that Al–Cu–Sc/B4C nanocomposites are promising lightweight and lead-free candidates for shielding against mixed gamma and neutron radiation. Their low density and the absence of toxic lead support potential applications in medical radiation facilities, nuclear technology systems, aerospace platforms, and industrial radiation environments where both radiation protection and weight reduction are important.
- MakaleYalnız künye2026Assessment of gamma-ray attenuation properties in advanced ceramics incorporating colemanite, pyrophyllite, and plastic clay
Uysal, Turan; Kaya, Selim
This study investigates the gamma-ray and neutron shielding performance of advanced ceramic composites containing colemanite, pyrophyllite, and plastic clay as environmentally friendly alternatives to conventional lead-based shielding materials. Gamma-ray attenuation properties were evaluated over the energy range of 59.54–2000 keV using theoretical calculations from WinXCOM and Monte Carlo simulations performed with the EGS4 code. Excellent agreement between the two methods confirmed the reliability of the simulation results. The mass attenuation coefficient (μ/ρ) decreased with increasing photon energy due to the transition from photoelectric absorption to Compton scattering and pair production mechanisms. Correspondingly, the half-value layer (HVL) and mean free path (MFP) increased, while radiation protection efficiency (RPE) decreased with photon energy. The effective atomic number (Zeff) exhibited an energy-dependent decline, reflecting changes in dominant photon–matter interaction processes. Neutron shielding performance improved with increasing colemanite content owing to the presence of boron-rich phases, and Sample-5 exhibited the highest fast neutron removal cross-section (ΣR = 0.11062 cm−1). The same sample also showed the highest gamma-ray kerma coefficients, indicating enhanced energy absorption capability. Overall, the results demonstrate that colemanite-enriched ceramic composites provide effective combined gamma-ray and neutron shielding and represent promising, sustainable, and non-toxic alternatives for radiation protection applications.
- MakaleAçık Erişim2026Long-term decline of Chernobyl-derived 137Cs in mosses and lichens from the Eastern Black Sea region of Türkiye
Çevik, Ugur; Çelik, Necati; Uzun, Kubra K.; Çelik, Ahmet; Koz, Bahadir; Özen, Songul A.; Yesilkanat, Cafer M.; Hacisalihoglu, Aylin; Özkalayci, Fatih; Kaya, Selim
This study presents the third consecutive assessment of 13 Cs activity concentrations in the same 50 moss (7 species) and lichen (2 species) sampling points in Ordu province, T & uuml;rkiye, one of the most heavily contaminated areas following the Chernobyl accident. Samples were collected from exactly the same locations used in the 1997 and 2007 studies and analyzed by high-resolution gamma spectrometry. In 2025, detectable 13 Cs was found in 14 of 30 moss sites (47%) and 3 of 20 lichen sites (15%). For samples below the minimum detectable activity (MDA), a value of MDA/2 (0.93 Bq kg-1) was substituted for lichens, while moss samples below the MDA were excluded from regression. The ecological half-life (Teco) for the 2007-2025 period was 4.38 +/- 1.05 years for mosses and 4.18 +/- 0.61 years for lichens. For mosses, this is nearly identical to the 1997-2007 mean (4.4 years), while for lichens it decreased from 5.6 to 4.18 years, suggesting a slight acceleration in environmental removal. All Teco values remain far shorter than the physical half-life of 13 Cs (30 years), confirming that environmental removal processes dominate over radioactive decay. Residual 13 Cs is concentrated in higher-altitude areas, reflecting the original deposition pattern and slower removal in cooler, more humid microenvironments. Nearly 39 years after the accident, the radiological risk posed by residual trace levels is negligible. This 28-year dataset provides one of the longest continuous records of 13 Cs in epiphytic bioindicators and serves as a valuable baseline for future contamination events.
- MakaleYalnız künye2026Computational gamma-ray attenuation and fast-neutron removal cross-section assessment of CrN, AlCrN and AlTiCrN ceramic coatings using EGS4 Monte Carlo and Phy-X/PSD
Sirin, Murat; Kaya, Selim; Aktarer, Semih Mahmut; Baltas, Hasan; Küçükömeroglu, Tevfik
In this study, the computationally predicted gamma-ray attenuation behavior and fast-neutron removal cross-section characteristics of micrometre-scale CrN, AlCrN, and AlTiCrN ceramic coatings produced via cathodic arc evaporation were investigated. The shielding parameters were not measured by direct gammaor neutron-transmission experiments; instead, mass attenuation coefficients (MAC, mu/rho) in the 0.05-2.50 MeV range were obtained from EGS4 Monte Carlo simulations and Phy-X/PSD calculations, and the agreement between the two computational datasets was evaluated. Energy-dependent attenuation parameters, including half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), radiation protection efficiency (RPE), and kerma coefficients, were calculated. Statistical comparison showed good consistency between EGS4 and Phy-X/PSD for MAC, RPE, HVL, MFP, and kerma coefficients, whereas Zeff exhibited larger method-dependent deviations. All coatings showed higher attenuation at low photon energies due to the photoelectric effect, while Compton scattering dominated at intermediate energies. Among the investigated coatings, CrN exhibited the most favorable calculated gamma-ray attenuation indicators, with lower HVL and MFP values and higher RPE values. The macroscopic fast-neutron removal cross-section (Sigma R) was also calculated as a first-order neutron attenuation indicator, and CrN showed the highest Sigma R value. Considering their limited thickness of approximately 2.3-2.8 mu m, these coatings should not be regarded as replacements for conventional bulk radiation shields. Instead, nitride-based ceramic coatings may serve as secondary or multifunctional surface layers in space-restricted components requiring local radiation attenuation and mechanical durability.
- MakaleAçık Erişim2025Investigation of Radiation Shielding Performance in Borosilicate Ceramic Glass Samples
Kaya, Selim
Ceramic glass is a multipurpose solid-state material that merges the high thermal stability, mechanical strength, and chemical durability of ceramics with the transparency, light transmission, and aesthetic benefits of glass. Because of these qualities, ceramic glass can be used in both industrial and scientific settings, especially when radiation protection, high-temperature endurance, heat resistance to thermal fluctuations, and optical clarity are required. Radiation shielding properties of five distinct ceramic glass samples with the chemical formula B2O3-ZnO-K2CO3-PbO (abbreviated as BZKP) were comprehensively assessed in this study. The radiation protection parameters of B2O3-ZnO-K2CO3-PbO glass-ceramic systems, including gamma-ray kerma coefficients (kγ), half-value layer (HVL), radiation shielding efficiency (RPE), mean free path (MFP), fast neutron macroscopic cross section ΣR (cm−1), and effective atomic number (Zeff), were theoretically examined using Monte Carlo EGS4 and WinXCOM software. The radiation shielding characteristics at 20 discrete photon energies, ranging from 0.05 MeV to 2 MeV, were theoretically calculated using the EGS4 simulation code and subsequently compared with data obtained from the XCOM program. The results of this study provide solid and valuable information regarding the improved design of high-performance ceramic glasses for radiation shielding applications. To create effective shielding solutions, a comprehensive understanding of the interactions between various materials and ionizing radiation, such as neutrons and gamma rays, is essential. By combining these discoveries, scientists can create new shielding materials that make the most of materials in these critical areas while improving radiation protection.
- MakaleAçık Erişim2025A comprehensive analysis of the effect of BaO incorporation on Gamma-Ray attenuation characteristics in SiO₂-B₂O₃-SrO-ZrO₂ glass systems
Kaya, Selim
This work presents an analysis of the effect of BaO incorporation on the gamma-ray attenuation properties of systematically evaluated SiO₂-B₂O₃-SrO-ZrO₂ glass matrices. Radiation shielding parameters determined using XCOM and EGS4 calculation codes were compared. There was an increase in glass density from 5.84 g/cm3 to 6.32 g/cm3 when the BaO content rose from roughly 10% to 40%. Using sophisticated WinXCom and EGS-4 calculations, the mass attenuation values (µ/ρ) of BaO doped SiO₂-B₂O₃-SrO-ZrO₂ glass systems (abbreviated BaSiBSZ) were found. This study systematically and thoroughly evaluated the effect of BaO integration on the radiation shielding capabilities of the glass system over a wide range of gamma-ray photon energies, specifically between 59.5 keV and 1332 keV. Initially, HVL (half-value layer) and MFP (mean free path) values were derived from the calculated mass attenuation coefficients. The evaluation of several crucial shielding parameters, including RPE, Zeff, ΣR, and kγ, came next. The steady reduction of SrO oxide concentration and substitution of BaO in BaSiSBZ glass systems resulted in notable modifications in radiation protection properties. The BaSiBSZ glass systems showed a similar decrease in both HVL and MFP at a constant energy level as the BaO doping concentration was progressively raised. Concurrently, a notable enhancement was noted in RPE, Zeff, ΣR, and kγ coefficients. The results demonstrate that higher BaO concentrations greatly enhance the material's radiation-shielding capabilities, enhancing both photon and neutron attenuation and bolstering the overall performance of the glass system.
- MakaleYalnız künye2023Calculation of radiation shielding parameters of YBa2Cu3O7 and Y3Ba5Cu8O18 superconductors for the energies from 122 to 1332 keV using EGS4 code
Kaya, Selim
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.
- MakaleAçık Erişim2023Calculation of the Effects of Silver (Ag) Dopant on Radiation Shielding Efficiency of BiPbSrCaCuO Superconductor Ceramics Using EGS4 Code
Kaya, Selim
In the current study, the effects of silver (Ag) additive on the radiation shielding efficiency of BiPbSrCaCuO superconducting ceramics was calculated using the EGS4 code and discussed theoretically by comparison with XCOM data. The mass attenuation coefficients (µ/ρ) for BiPbSrCaCuO superconductor ceramics and their contents were investigated theoretically (WinXcom and EGS4) at gamma-ray energies ranging from 59.5 to 1332 keV. The theoretical values were computed in the energy range from 1 keV to 100 MeV using the WinXcom program. Then, using the mass attenuation coefficients, some shielding parameters were determined, such as the mean free path (MFP), the half value layer (HVL), the effective atomic number (Zeff), the radiation protection efficiency (RPE), the macroscopic fast neutron removal cross-sections (ΣR, cm−1) and the gamma-ray kerma coefficients ((Formula presented.)). Theoretically, the results obtained with XCOM and EGS-4 were found to be in good agreement. The radiation shielding efficiency (RPE), neutron removal cross-section (ΣR, cm−1), maximum and semi-valent layer (HVL), and mean free path (MFP) values were found to be smaller for BiPbSrCaCuO superconducting ceramics as the silver (Ag) contribution was increased. Data from this study can guide further research and development of shielding materials for gamma-ray and neutron shielding.
- MakaleYalnız künye2023Effect of detector crystal size on Compton suppression factors
Kaya, Selim; Çelik, Necati; Gök, Abdulkadir; Çevik, Uğur
The geometrical parameters which affect the suppression factor for an HPGe (High Purity Germanium)-NaI Compton suppression spectrometer were studied by a Monte Carlo simulation with the EGS4 system. The spectrums were crated for 5 energy values ranging from 200 keV to 2 MeV. Compton suppression factors (CSFs), the parameters characterizing the system performance, were calculated for different HPGe crystal parameters. It was observed that to obtain better Compton suppressed factors, a laboratory must choose as small HPGe crystal as possible for energy values up to 400 keV. However, for higher energies up to 2 MeV, larger HPGe crystals provide better Compton suppression systems. These findings suggest that the choice of HPGe crystal size can significantly impact the performance of a Compton suppression spectrometer and should be carefully considered in its design and optimization.
- MakaleAçık Erişim2022Doğu Karadeniz Bölgesi Sahil Otoyol Çevresindeki Karayosunlarında Trafik Kaynaklı Ağır Metal Analizleri
Kaya, Selim; Koz, Bahadir
Bu çalışmanın amacı; Giresun-Samsun otoyol çevresindeki karayosunları kullanılarak Trafik kaynaklı ağır metal kirliliğini belirleyebilmektir. Karayosunları, ağır metalleri biriktirebilme yeteneğinden dolayı, ağır metal hava kirliliğinin belirlenmesinde oldukça uygun biyoindikatörlerdir. Türkiye’nin Doğu Karadeniz bölgesinde yer alan Giresun-Samsun otoyolu çevresindeki karayosunlarının ağır metal analizleri InductivelyCoupledPlasma–MassSpectrometer (ICP-MS) cihazı kullanılarak belirlendi. Karayosunlarının kalitatif analizleri neticesinde Cr, Fe, Mn, V, Zn, Cu, Ni, Pb ve Co olduğu belirlendi. Şehir merkezlerinden toplanan karayosunlarındaki konsantrasyon değerleri sırasıyla 15.12, 6087.31, 301.12, 27.80, 74.20, 38.48, 56.69, 19.40 ve 9.10, mg/kg olarak belirlenirken, şehirler arasından toplanan karayosunlarının ağır metal konsantrasyonları ise 15.56, 4751.23, 247.93, 28.03, 83.71, 33.72, 48.38, 17.20 ve 6,97 kg/kg olarak belirlendi. Genelde karayosunlarında, Krom(Cr), Demir(Fe), Mangan(Mn), Vanadyum(V), Çinko(Zn), Bakır(Cu), Nikel(Ni), Kurşun(Pb) ve Kobalt(Co)’ınkonsantrasyonlarının 2006 ve 2017 yılları arasında azaldığı görüldü. Fakat bu azalmaya rağmen karayosunlarındaki ağır metal konsantrasyonları hala yüksektir.
- MakaleYalnız künye2022Effect of front, lateral and back dead layer thicknesses of a HPGe detector on full energy peak efficiency
Kaya, Selim; Çeli̇k, Necati; Bayram, Tuncay
As well known, High Purity Germanium (HPGe) detectors have a wide range of applications in every area where radiation detection and measurements are involved. One of the most important parameters in this respect is the determination of the full energy peak (FEP) efficiency. There are certain parameters affecting the so-called FEP efficiency. Perhaps the most important one is the thickness of dead layers of the crystal itself. In the current study, we investigated the effects of the thickness of front, lateral and back dead layer thicknesses of the detector crystal on the FEP efficiencies for the energy range 30 keV–5 MeV using EGS4 Monte Carlo simulation package. It was shown that the change in the thickness of the front dead layer has significant effect on the efficiency values for the energy interval 30–400 keV. The change in the thickness of the lateral and back dead layer was shown to have significant effects on the efficiencies for the energy intervals 2–3 MeV and 3–5 MeV, respectively. The results were checked using GEANT4 and a good agreement was observed.
- MakaleYalnız künye2020Determination of the environmental natural radioactivity and mapping of natural background radioactivity of the Gumushane province, Turkey
Kaya, Selim; Kaya, Ali; Çelik, Necati; Kara, Rasim Taylan; Taşkın, Halim; Koz, Bahadır
The aim of the study is to determine the ambient radiation level in Gumushane province. With this aim, the gamma dose ratios absorbed in the air were surveyed by a portable gamma detector. The activity concentrations of 226Ra, 232Th, 40K, and 137Cs in soil samples have been measured by the gamma spectrometric analysis system. The gross alpha and beta activity concentrations in drinking water were also determined by the alpha and beta counting system. By considering the geological structure, the soil samples have been obtained from 62 different spots. In addition, 77 samples of natural and tap water have been collected from different points of the province. The samples were analyzed at the Cekmece Nuclear Research and Training Center in Turkey. Absorbed gamma dose rates in the air were measured in 338 different points in the studied area.
- MakaleYalnız künye2016Gümüşhane Merkez ve Merkeze Bağlı Bahçecik Köyü Su Kaynaklarının Radyoaktivitesinin Tayini
Kaya, Selim; Karabidak, Salih Mustafa; Kaya, Ali
Bu araştırmada, Gümüşhane ili Bahçecik köyü yayla bölgesi, Gümüşhane merkez ve merkeze bağlı Bahçecik köyü şebeke sularının radyoaktivitesinin belirlenmesi amaçlanmıştır. Bu çalışma, içme suyu olarak kullanılan kaynak suların insan sağlığına zararlı miktarda radyoaktivite taşıyıp taşımadığının belirlenmesi ve Bahçecik köyü yayla bölgesine yapılacak içme suyu barajından Gümüşhane ili içme suyunun karşılanmasının planlanması bakımından önemlidir. Çalışmada, bölgedeki kaynak sularından alınan numunelerin toplam Alfa-Beta analizleri Türkiye Atom Enerjisi Kurumu İstanbul Küçükçekmece'deki araştırma merkezine gönderilerek orada yapılmıştır. Gama analizleri ise Üniversitemiz laboratuvarlarında yapılmıştır. Elde edilen sonuçlar toplam Alfa Bahçecik yayla bölgesinde en düşük ve en yüksek; <10 mBq/L ve <20 mBq/L toplam Beta da 13 ±1 mBq/L ve 50±10 mBq/L belirlenmiştir. Bahçecik köyünde çeşmede toplam Alfa 40±10 mBq/L ve şebeke suyunda <10 mBq/L toplam Beta çeşmede 70±10 mBq/L ve şebeke suyunda 50±10 mBq/L olarak belirlenmiştir. Gümüşhane merkez şebeke suyunda ise iki noktadan alınan numuneler için toplam Alfa değerleri sırasıyla 30±10 mBq/L ve 40±10 mBq/L ve toplam Beta değerleri 112±10 mBq/L ve 118±10 mBq/L olarak belirlenmiştir. Analiz sonuçlarında belirlene toplam Alfa-Beta değerlerinin üç bölgede de insan sağlığına zarar verecek değerler olan toplam Alfa'da 0.5 Bq/L, toplam Beta'da 1 Bq/L'nin altında olduğu görülmektedir. Gama analizinden elde edilen sonuçlara göre, 226Ra için 4.6 mBq/L ile 5.5 mBq/L, 232Th için 2.1 mBq/L ile 3.6 mBq/L; 40K içinde 91.25 mBq/L ile 117.9 mBq/L aralığında olduğu belirlenmiştir. Bu değerler için hesaplanan yıllık etkin doz eşdeğerleri, Dünya Sağlık Örgütünün (WHO) içme suları için belirlediği yıllık etkin doz eşdeğerinin üst sınırı olan 0.100 mSv/y'in çok altındadır. Gümüşhane ili şebeke suyu, Bahçecik köyü şebeke suyu ve Bahçecik köyü yayla bölgesindeki doğal su kaynaklarının insan sağlığına zarar verecek derecede radyoaktivite taşımadığı tespit edilmiştir
- MakaleYalnız künye2016X ve Gama-Işını Dedektörlerinde Ölü Zaman Düzeltmesi İçin Bir Program
Bingöl, Özkan; Kaya, Selim; Karabidak, Salih Mustafa; Kaya, Ali
X ya da gama ışını detektörlerinin kullanıldığı spektrometrik kantitatif ve kalitatif analizlerinde, analizlerin doğruluğu için sayma kayıplarının belirlenmesi ve telafi edilmesi önemlidir. Spektrometrelerdeki bu sayma kayıpları uzatılan ve uzatılmayan sistem ölü zamanlarından meydana gelir. Bu çalışmada, bu kayıpları telafi etmek için bir bilgisayar program geliştirilmiştir. Programı test etmek için deneysel çalışmalar yapılmıştır. Program, DELPHI program derleyicisiyle kodlanmıştır. Program, ölü zaman düzeltme, özgün pik arama, özgün grafik modülü, yazılım arayüzü ve program sonucunu rapor halinde veren rapor modüllerden oluşmaktadır. Bu programda düzeltme yapılmamış veya düzeltme yapılmış spektrumları ayrı ayrı irdeleme imkânı sağlanmıştır
- MakaleYalnız künye2015Gümüşhane İli Çevresinde Toplanan Toprak ve Karayosunu Örneklerinde Doğal (226Ra, 232Th ve 40K) ve Yapay (137Cs) Radyoaktivite Konsantrasyonlarının Belirlenmesi
Kaya, Selim; Karabidak, Salih Mustafa; Çevik, Uğur
Bu çalışmanın amacı, Gümüşhane çevresinde toplanan toprak ve karayosunu örneklerinde doğal (226Ra, 232Th ve 40K) ve yapay (137Cs) radyoaktivite konsantrasyonlarını belirlemektir. Gümüşhane çevresinde toplanan toplam 28 (12 karayosunu,16 toprak) toprak ve karayosunu örnekleri analiz edilmiştir. Gümüşhane ili çevresinde toplanan toprak ve karayosunu örnekleri için doğal ve yapay radyoaktivite konsantrasyonları iyi kalibre edilmiş yüksek çözünürlüklü germanyum dedektörü (HPGE dedektörü) ile belirlenmiştir. Gümüşhane ilindeki toprak ve karayosunu örneklerinde aktivite konsantrasyonları 226Ra için 17,31 ile 141,62 Bqkg-1 arasında, 232Th için 9,70 ile 35,34 Bqkg-1 arasında ve 40K için 236,83 ile 1039,11 Bqkg-1 arasında bulunmuştur. Doğal radyoaktivitenin yanısıra yapay 137 Cs aktivite konsantrasyonu toprak ve karayosunu örneklerinde ölçülmüştür. Toprak örnekleri için 137 Cs aktivite konsantrasyonu 7,63 ile 39,44 Bqkg-1 arasında, karayosunu numuneleri için 12,45 ile 196,89 Bqkg-1arasında bulunmuştur. Elde edilen değerler kullanılarak toprak ve karayosunu için sırasıyla ortalama eşdeğer radyum aktivitesi değerleri (Raeq) 96 Bqkg-1 ve 157 Bqkg-1 bulunmuştur. Ölçülen örneklerin Raeq değerleri; eşdeğer gama doz oranı 1,5 mSv.y-1 denk gelen 370 Bqkg-1 limit değerinden çok düşüktür.