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In this study, energy resolution dependent on K-Parameters (Trapezoidal filter system optimizing the count rate) of EXOGAM2 detector with newly developed NUMEXO2 digital electronics using 152Eu radioactive source measured and analysed. This experimental study was carried out at the GANIL (Grand Accelerature National d'Ions Lourd) nuclear research center in France. The measurement and analysis results for different K parameters using a 152Eu radioactive source with low and high gamma energy levels were performed for two EXOGAM2 detectors. Without applying any K parameter, the resolution values expressed by FWHM for the 1.EXOGAM2 detector are measured as 2.360% FWHM for (344.2785 keV), 2.820% FWHM for (1408.006 keV), and 2.451% FWHM for (344.2785 keV), 2.975%FWHM for (1408.006 keV) for the 2.EXOGAM2 detector, respectively. For different K parameters (K=2µs, K=5µs ve K=10µs) detail results are shown below., Bu çalışmada, yeni geliştirilen dijital elektronik NUMEXO2 dijital elektronik ile EXOGAM2(EXOtic GAMma array spectrometer) dedektörünün K-Parametrelerine (sayım oranını optimize eden Trapezoidal filtre sistemi) bağlı enerji çözünürlüğü için 152Eu radyoaktif kaynak kullanılarak ölçüm ve analiz yapılmıştır. Yapılan bu deneysel çalışma Fransa’da bulunan GANIL (Grand Accelerature National d’Ions Lourd) nükleer araştırma merkezinde gerçekleştirilmiştir. Düşük ve yüksek gama enerji seviyesine sahip 152Eu radyoaktif kaynak kullanılarak farklı K-parametreleri için gerçekleştirilen ölçüm ve analiz sonuçları iki EXOGAM2 dedektörü için gerçekleştirilmiştir. Herhangi bir K-parametresi uygulamadan 1.EXOGAM2 dedektörü için FWHM ile ifade edilen çözünürlük değerleri sırası ile (344. 2785 keV) için 2.360% FWHM, (1408.006 keV) için 2.820% FWHM olarak ölçülürken 2.EXOGAM2 dedektörü için ise sırasıyla 2.451% FWHM ve 2.975% FWHM olarak ölçülmüştür. Farklı K-parametreleri (K=2µs, K=5µs ve K=10µs) için ise sonuçlar detayları ile aşağıda gösterilmiştir.

A code is developed to correct for the coincidence summing effect in detecting a voluminous gamma source, and this code is applied to a152Eu standard source as a test case. The source is 1000 mL of liquid in a cylindrical shape. To calculate the coincidence summing effect, the cylindrical source is considered as 10(radial) × 8(height) sectional sources. For each sectional source, the peak efficiency and total efficiency are obtained by Monte Carlo simulation at each energy for 10 energies between 50 keV and 2000 keV. The efficiencies of each sector are then expressed as polynomials of gamma energy. To calculate the correction coefficients for the coincidence summing effect, the KORSUM code is used after modification. The magnitudes of correction are 4%–17% for the standard 152Eu source measured in this study. The relative deviation of 4.7% before the coincidence correction is reduced to 0.8% after the correction is applied to the efficiency based on the measured gamma line. Hence, this study has shown that a new method has been developed that is applicable for correcting the coincidence effect in a voluminous source, and the method is applied to the measured data of a standard 152Eu cylinder source.

Using a portable microcomputer multi-channel gamma spectrometer to directly measure the radioactive content in the soil, the on-site gamma energy spectrum measurement was carried out on the soil of 7 parks in a certain city. The survey results show that the specific activity of 40k in the urban park soil ranges from 470.88 bq/kg to 640.2 bq/kg. The specific activity of 238u ranges from 26.77 bq/kg to 33.31 bq/kg. The specific activity of 232th ranges from 42.14 bq/kg to 54.72 bq/kg. The content of the three radionuclides in the soil in the park is lower than the national average, and far lower than the radioactivity of ordinary building materials.

Transparent heavy metal oxide glasses are becoming increasingly important because of their effectiveness in reducing unwanted occupational and public radiation exposure in the medical settings; and for the clear view it offers when properly used during the construction of diagnostic radiology facilities, mobile shields and eye wears. WinXCom computer program was used to determine the mass attenuation coefficients of the studied glass systems; while other shielding parameters were determined by using appropriate equations. All these shielding parameters were determined at 20 keV, 30 keV, 40 keV and 60 keV; these are the average energies of photons commonly used in diagnostic radiology. The outcome of this work shows that increment in Bi2O3 led to better MAC and HVL at 20 and 30 keV while increment in TeO2 led to better MAC and HVL at 40 and 60 keV B1, B3 and B4 showed different improved shielding properties at 20, 40 and 60 keV zBi2O3–30B2O3-(70-z) TeO2 glass system showed better shielding qualities when compared with commonly used materials in diagnostic radiology.

IIn this study, pure silicone rubber and iron ore concentrate added silicone rubber materials were performed against Cs-137 gamma source. Cs-137 is accepted medium energy level gamma source in nuclear technology. Up to 67 wt. % iron ore concentrate added into silicone rubber materials were used in the experiments. Linear attenuation graphs were carried out for the studied samples against Cs-137 gamma source which has unique peak at 0.662 MeV energy. Increasing iron ore ratio in the materials caused the higher radiation shielding performance for Cs-137 gamma source. In addition, increasing iron ore ratio decrease the total volume air bubbles in the samples. Decreasing air bubbles in the samples has contributed to gamma ray shielding. 0.5 mmPbE and 1 mmPbE Lead equivalent (PbE) values were determined for the samples. 0.5mmPbE standard has been provided by using 2.83 mm thick of 67 wt. % iron ore concentrate imbedded silicone rubber at 0.662 MeV gamma energy. In conclusion, iron ore concentrate imbedded silicone rubber materials are among the promising economic radiation shielding materials which could be alternative to lead.

Radioisotope indium-113m ( 113m In) with half-life, T 1/2 = 1.7 hours and gamma energy, Eg = 391 keV is suitable and meets the criteria as radiotracer in industry. 113m In radioisotope was obtained from tin-113 decay ( 113 Sn, T 1 / 2 = 115 days) of 112 Sn (n,g) 113 Sn neutron activation in nuclear reactor. The process of separation of radioisotope 113m In using column chromatography method based on silica gel matrix using 0.05 M HCI solution. Radionuclide and radiochemical purity tests were performed using the gamma-spectrometry method and paper chromatography. The final product specification in the form of 113m InCl 3 is clear solution, pH 2, obtained yield of 81.83%, radionuclide purity of 90.22%, radiochemical purity of 91.61 ± 0,29% and stable for 3 days at room temperature.

Gamma-ray shielding effectiveness of different types of natural marble tiles commonly used for cladding the exterior walls of residential and non-residential buildings in Riyadh, Saudi Arabia has been investigated in the energy range 59.5–1332.5 keV. To this end, linear attenuation coefficients (μℓ) have been obtained by applying narrow-beam technique. Mass attenuation coefficient (μm), transmission factor (TF) and half-value layer (HVL) have been employed to study the shielding performance of marbles and also compared with those of calcite. The experimental findings revealed that HVL parameter correctly determined the shielding effectiveness of the dissimilar types of marble. Compared with other marbles, Carrara marble (Italy) showed preferable shielding effectiveness. Moreover, a formula, μm = aE−b, was proposed to evaluate and compare the shielding properties of the marble tiles over a broad energy range. In this formula, a and b were determined empirically. In conclusion, natural marble proves to be more reliable in reducing gamma radiation when used for external building cladding than ordinary concrete, and it could be a good alternative to lead shield against high gamma energy because it is 24% heavier than lead. Keywords: Gamma-ray shielding effectiveness, Attenuation coefficients, HVL, Transmission factor, Natural marble

The characteristic parameters of a material relation to photon interactions such as: mass attenuation coefficient, effective atomic number, effective electron density are required to provide essential data in diverse works such as nuclear diagnostic and cancer radiotherapy, industrial irradiation, radiation dosimetry, radiation protection and shielding, analyzing of the concentration of elements and radioactive isotopes. In this paper, the theoretical models such as non-relativistic form factor (NRFF), relativistic form factor (RFF), and modified form factor (MFF) were used to calculate the ratio Rayleigh-Compton for elements with at gamma energy 59.5 keV. The results showed that there was a discrepancy between the theoretical modes at a high atomic number. The mean value of the Rayleigh-Compton ratio depends on the atomic number, which shows the quadratic function of the correlation coefficient R2 = 0.996 as well. Besides, the experimental system was set-up and measured for some targets such as aluminum, copper, and lead at a scattering angle 150o using 241Am source by Si(Li) detector to confirm the theoretical values. The preliminary result showed that there was a good agreement with experimental and theoretical results is lower than 20%. Further investigation will be measured by the samples for more detailed evaluation.

Gamma energy spectrum is a way to confirm the type and content of radioactive nuclides in substances. In order to obtain effective data of gamma spectrum, it is necessary to analyze the data of gamma spectrum obtained by the detector. Nevertheless, due to the influence of statistical fluctuation and gamma generated by the environment itself during the measurement of gamma spectrum, the obtained gamma spectrum is not accurate enough as a result of needing spectral analysis of gamma spectrum, and noise reduction can make the spectral data smoother. Therefore, this paper studies the noise reduction algorithm for gamma spectrum analysis, analyzes the design and application of different algorithms in the process of noise reduction, and summarizes the advantages and disadvantages of this algorithm and others.

In the present work, several commonly used aluminum alloys were investigated for their protective properties against gamma radiation. The gamma transmission technique was used to study the gamma attenuation behavior of the alloys. Cs-137 (0.662 MeV) and Co-60 (1.25 MeV) gamma radioisotope sources, which have relatively medium and high gamma energy levels, were used as gamma sources. The linear and mass attenuation coecients of the aluminum alloys were measured. The mass attenuation coecients of the samples were compared with the theoretical values which were calculated using XCOM computer code. The dierence between the experimental and theoretical values was below 5%. In addition half-value layer (HVL) values for the studied aluminum alloys were calculated using the linear attenuation coecients. The attenuation coecients of the dierent aluminum alloys were compared. The biggest HVL was observed for 1050 alloy, for both gamma isotope sources, which means the smallest gamma attenuation capability among the studied alloys. It is concluded that the alloys were applicable for the gamma radiation shielding applications.

The fibrous self-compacting concrete is a high performance concrete with uniformly distributed iron fibers, developed and characterized by Maragon (2006 and 2009). Transmission measurements, with 137Cs and 60Co sources were performed for the attenuation coefficients determination for both ordinary and fibrous self-compacting concretes. The results were compared to each other and to the values found in the literature for ordinary concrete. The mass attenuation coefficient for the fibrous self-compacting concrete showed to be higher than those for ordinary concrete of about 5%, depending on the gamma energy. However, it should be noted that the density of fibrous self-compacting concrete is higher than ordinary concrete, 2.4 g/cm3 and 1.9 g/cm3 respectively, increasing still further the difference in mass attenuation coefficient. In addition to that, by using Monte Carlo simulations, with MCNP5 Monte Carlo computer code, the data was extended to the 50-3000 keV gamma energy range.

Compton-suppression spectrometer is well suited to the analysis of low levels of radioactive nuclides. Monte Carlo simulations can be a powerful tool in calibrating these types of detector systems, provided enough physical information on the system is known. A simplified Compton-suppression spectrometer model using the Geant–4 simulation toolkit was discussed. The spectrometer model was tested to evaluate photo peak efficiency of detecting point and disk sources. The efficiency calibration was calculated for incident gamma energy from 200 to 3000 keV in both the suppressed and unsuppressed mode of operation. The applicability of the efficiency transfer method in various measurement geometries was tested successfully. It can save time and avoid tedious experimental calibration for different samples geometries. Key words: Compton-suppression spectrometer, photopeak efficiency, Geant–4 Monte Carlo simulation Compton-suppression spectrometer, photopeak efficiency, Geant–4 Monte Carlo simulation.

The properties of the ground, beta and negative parity state bands of 146Nd–156Nd isotopes have been studied. The ratio of gamma energy over spin has been calculated and drawn as a function of spin (I) to show the ground-state evolution for each isotope. The ratio between the excitation energies of successive (I+2) and (I) states as a function of spin (I) has been calculated and drawn to determine the property of the ground-state bands of 146Nd–156Nd isotopes. The odd-even staggering has been drawn to determine the energy difference of the states of the ground-state bands and the negative-parity bands. The energy levels for the ground-state band of 146Nd–156Nd have been calculated using the Bohr-Mottelson Model, the Interacting Boson Model, the Interacting Vector Boson Model and the Doma–El-Gendy Relation. The energy levels of the beta band for the measured experimentally levels of 148Nd, 150Nd and 152Nd have been calculated using the Interacting Boson Model. The energy levels of the negative parity band of the 146Nd, 148Nd, 150Nd, 152Nd and 156Nd isotopes have also been calculated using the Bohr-Mottelson Model and the Interacting Vector Boson Model. The calculated energy levels compared with the experimental data indicate the quality of the fit presented in this paper.

The particular physics of Laser Produced Plasmas (LPP) needs some diagnostic requirements. Specifically, the X-ray monitoring of the plasma is known to be difficult since typically X-ray emissions are concentrated in bursts from a few tens of ps to few ns, based on the power and pulse time width of the laser. Therefore, the energy measurement of the radiation coming from a single experimental run is basically unfeasible using conventional techniques. Additional particles can be produced from LPP experiments, especially high energy gamma photons and electrons. As a case study in recent experiments, carried out on VEGA-2 laser facility (CLPU, Salamanca, Spain), the aim was to produce neutrons through photonuclear reactions on different types of solid targets. We have used the Timepix3 chip, in a "side-on" configuration, in order to produce a quick estimate of the gamma photons energy involved in the reactions. This detector, based on silicon, is realized with a single chip of 256 × 256 pixels bump-bonded with a 14 mm × 14 mm × 300 μm silicon layer. Interaction of gammas with the detector in this configuration produces some characteristic clusters of pixels and, for each cluster, a variety of physical and morphological parameters can be defined. Based on some of these parameters, we have characterized the detector response using some known laboratory gamma sources and the related Geant4 simulations. This allows quick energy discrimination for the gamma photons coming from different experimental runs.

Data on nuclear level densities extracted from transmission data or gamma energy spectrum store the basic statistical information about nuclei at various temperatures. Generally this extracted data goes through model fitting using computer codes like CASCADE. However, recently established semiclassical methods involving no adjustable parameters to determine the level density parameter for magic and semi-magic nuclei give a good agreement with the experimental values. One of the popular ways to paramaterize the level density parameter which includes the shell effects and its damping was given by Ignatyuk. This damping factor is usually fitted from the experimental data on nuclear level density and it comes around 0.05 $MeV^{-1}$. In this work we calculate the Ignatyuk damping factor for various nuclei using semiclassical methods., Comment: 9 Figures, 1 Table

International audience; One of the features of the spectra obtained by airborne gamma spectrometry is the low counting statisticsdue to a short acquisition time (1 s) and a large source-detector distance (40 m) which leads tolarge statistical fluctuations. These fluctuations bring large uncertainty in radionuclide identification anddetermination of their respective activities from the window method recommended by the IAEA,especially for low-level radioactivity. Different types of filter could be used on spectra in order to removethese statistical fluctuations. The present work compares the results obtained with filters in terms oferrors over the whole gamma energy range of the filtered spectra with the window method. These resultsare used to determine which filtering technique is the most suitable in combination with somemethod for total stripping of the spectrum.

The recently developed Cs2LiYCl6:Ce (CLYC) crystals are interesting scintillation detectors not only for their gamma energy resolution (

Gamma attenuation coefficients of host rocks belonging to Moghra Formation of Eocene era in one of two candidate sites located at the North Western Coast of Egypt in Al-Dabaa locality were estimated using Monte-Carlo Code for Nuclear Power (MCNP). Carbonates rock samples were taken to represents several depth intervals. A virtual mono-energetic gamma source with increasing energies was used. The gamma attenuation properties were found to be totally independent on the lithology of rock type, provided that roch sample density remains constant. Ultimately it is found that, gamma attenuation coefficient showed an inverse exponential dependence on the gamma energy regardless rock type and their related depth.

Concentration of 212Bi, 212Pb and 228Ac were tracked at different time intervals for 33 days in IAEA-RGTh-1 reference material having 2.89% Th and soil collected from ambient environment. In case of reference material, mean concentration of 232Th evaluated using gamma energy line of 228Ac (912 keV) and 212Bi (728 keV) shows a deviation of only 0.05%, and 5.66% respectively from the certified mean value of 232Th, whereas a large negative deviation of 29.9% was observed in the case of 212Pb (239 keV). Th-232 concentration in soil sample as evaluated using above three different gamma lines shows a variation of only 10-13%.

The Compton Effect 1 is an ideal physics experiment for the advanced modern physics lab. The relevance of this experiment and an approach to teaching about this lab are discussed. The apparatus for this experiment consists of a Cs-137 gamma source located in a lead howitzer, a goniometer to precisely locate a NaI detector at different angles to make gamma energy measurements, and a multichannel analyzer system that includes a high voltage supply and amplifiers. The lead howitzer and goniometer were specially constructed, and information to reproduce them is given. Typical results are presented.

This study is aimed to assess the effect of the gamma ray of 511keV energy which is emitted from phantom where the positron emission radionuclide was injected on X-ray CT image. As a scanning method, the CT number and pixel value of the reference image where water was injected(0 mCi), and those acquired by changing the capacity of 18F(Fluorine), positron emission radionuclide, into 1 mCi, 2 mCi, 5 mCi, and 10 mCi were measured. As a result of measuring the CT number(HU) of the phantom image where the positron emission radionuclide() was injected, there were reference water ( HU), 1 mCi( HU), 2 mCi( HU), 5 mCi( HU), and 10 mCi( HU). Compared with the image where it was filled with water, there was a reduction of 5.89 Hu in 10 mCi, 3.73 in 5 mCi, 2.69 HU in 2 mCi, and 2 HU in 1 mCi. As for the pixel value of the phantom image, there were reference water (), 1 mCi(), 2 mCi(), 5 mCi(), and 10 mCi(). Compared with the reference image, there was a reduction of 5.50 in 10 mCi, 3.40 in 5 mCi, 3.10 in 2 mCi, and 2.02 in 1 mCi. Through this experiment, it was indicated that, with the increase in the dose of the positron emission radionuclide(), the CT number and the pixel value of the image reduced proportionally, and the width of reduction showed a similar value, too. Accordingly, according to the degree of change in X-ray CT image due to the positron emission radionuclide in the quality control item of PET/CT, the proper standard should be established and it should be periodically managed.

The aim of this study was to investigate the changes in identification markers of irradiated foods after treatment of the full-overlapped gravitational field energy (FGFE). Wheat and soybean samples were irradiated at 0-5 kGy of Co-60 gamma energy, and analyzed for photostimulated and thermo luminescence characteristics (PSL and TL) and sprouting rate at 0 and 6th month after FGFE treatment. As a screening method for irradiated samples, PSL photon counts (PCs) for the non-irradiated samples appeared negative (5,000 PCs). But FGFE-treated irradiated samples appeared intermediate (700-5,000 PCs), showing decreased PCs during storage. The TL analysis on irradiated samples exhibited glow curve peaks in range of and TL ratio () was also >0.1. Therefore, identification of irradiated samples was possible using thermoluminescence. But the glow curve range of FGFE-treated irradiated samples shifted from to and TL intensity was decreased 37-60% resulting from FGFE treatment. After 6 months of storage, all the samples showed a decrease in TL intensity, but identification was still possible. The sprouting rate of irradiated samples decreased by about 72%, whereas that of FGFE-treated irradiated samples showed by about 85%, as compared to non-irradiated samples. More detailed study is required to investigate sprouting phenomena for FGFE-treated samples.

The investigation of the environmental radioactivity around the radioactive waste disposal site in Gyeongju is being carried out. The radioactivity of I in groundwater and seaweed are to be measured. The analytical method to measure the radioactivity of I in aqueous media was established. This method contains oxidation-reduction reaction, anion-exchange separation and palladium precipitation. The I radioactivity in the PdI2 precipitates was measured by using low-energy gamma spectrometer. The counts of peak at 39.6 keV of gamma energy were used for determination of I radioactivity. The chemical recovery was determined by the weights of PdI2 precipitates. The deionized water and groundwater spiked with I tracer were tested. In the case of deionized water, the relative deviations of measured concentration from spiked one are from 1.1 to 10.7%. The relative deviations of measured radioactivity from spiked one in the groundwater experiments are 2.9 and 3.7%. The measured concentration is in good agreement with spiked one. The groundwater sampled from radioactive waste disposal site was tested. The concentrations of I in the groundwater are below minimum detectable activities of 36.7 and 36.6 mBq/L.

The clinical use of radioactivity centered upon diagnosis and therapy constitutes one of the greatest advances in non-invasive medicine. This medical field is called nuclear medicine. The nuclides of metallic elements abound in radionuclides used in nuclear medicine. For the diagnostic application, pure gamma ray-emitting short-lived radionuclides, which possess low gamma energy emission, are useful due to high permeability in the body, and radiometals such as 99mTc, 201Tl, 67Ga and 111In have received great attention for diagnostic applications. Another clinical application of radionuclides is the therapeutic field. Since therapeutic nuclear medicine involving the use of internally administered radionuclides bases on the damage of radiation from the radionuclide to the target component in the cell, beta particle emitters, which provide high radiation dose, are useful for this purpose. Some compounds labeled with metallic radionuclides such as 90Y, 89,90Sr, 186,188Re and 67Cu have received attention for therapy. These metallic radionuclides have received the most attention due not only to their nuclear physical characteristics, but also to their inherent capacity to coordinate with a great variety of ligands. This great versatility allows the rational design of radiometallic compounds that show high and specific localization in a target tissue, an essential requirement for nuclear medical use. This paper describe some examples of successful drug designing using radiometallic compounds for nuclear medicine. Better knowledge of physiology and a more rational use of bioinorganic chemical principles will contribute to the development of new radiometallic compounds for targeted diagnosis and therapy.

Gamma-ray multiplicities, individual gamma-ray energy spectra, and total gamma energy spectra following neutron-induced fission of 239 Pu were measured using the DANCE detector at Los Alamos. Correc- tions for detector response were made using a forward-modeling technique based on propagating sets of gamma rays generated from a paramaterized model through a GEANT model of the DANCE array and adjusting the parameters for best fit to the measured spectra. The results for the gamma-ray spectrum and multiplicity are in general agreement with previous results, but the measured total gamma-ray energy is about 10% higher. A dependence of the gamma-ray spectrum on the gamma-ray multplicity was also observed. Global model cal- culations of the multiplicity and gamma energy distributions are in good agreement with the data, but predict a slightly softer total-energy distribution.

Terrestrial Cerenkov Telescopes at tens GeV gamma energy and Scintillators set on a Crown-like array facing the Horizons may reveal far Cosmic Rays Showers or nearer PeVs Neutrino ν ¯ e - e → W - shower in air as well as up-going ν τ + N → τ + X , τ → Earth-Skimming tau air-showers. Even UHE SUSY χ o + e → e ˜ → χ o + e at tens PeVs–EeV energy may blaze at Horizons, as ν ¯ e - e → W - shower. We show first estimate on down- and up-going Horizontal Showers traces for present and future Magic-like Crown Arrays and their correlated Scintillator-like twin Crown Arrays. The one mono- or stereo-Magic elements facing the Horizons are already comparable to present Amanda underground neutrino detector.

The official method for the determination of iodine-131 in milk has a lower limit of detection (LLD) of 10 pCi/L (0.37 Bq/L). The Nuclear Regulatory Commission had recommended that a method claiming to have an LLD of

Coupled neutron-gamma shielding calculations using Sn transport theory can be time consuming, especially for two-and three-dimensional geometries. In general, the CPU time of these calculations increases stronger than linear with increasing number of neutron and gamma energy groups, and depends on the order of Legendre expansion and number of Sn directions used. This fact induced the idea of the decoupling method, which seems applicable to accelerate coupled neutron-gamma shielding calculations. The data included in a combined neutron-gamma library can be readily separated into a library containing neutron data only and another library containing gamma data only. Separate calculations for neutrons and gammas are performed on complex geometries using a different Legendre order expansion for neutrons and gammas. CPU savings of 60 to 85% can be achieved for the two-dimensional DORT and three-dimensional TORT calculations respectively.

We performed a number of comparative MCNPX simulations of gamma energy depositions of scintillation crystals with smooth and rough surfaces. In the study, nine surface patterns (8 micro-roughness + 1 smooth) were coupled with eight common scintillation crystals for a total of 72 possible combinations. Although this was a preliminary study, the outcome was counterintuitive; results generally favored surfaces with micro-roughness over a conventional smooth surface as measured in terms of average energy depositions. The advantage gained through surface roughness is less significant for CdSe and LaCl3, but is most significant for the common NaI and the glass-like SiO2 scintillators. Based on the results of the 64 rough-surface coupled MCNPX simulations, 57 of the 64 (~89%) simulations showed some improvement in energy deposition. The mean improvement in energy deposition was 2.52%. The maximum improvement was about 8.75%, which was achieved when roughening the surface of a SiO2 scintillator using a micro cutting pattern. Further, for a conventional NaI scintillator, MCNPX results suggest that any roughness pattern would improve the energy deposition, with an average improvement of 3.83%. Although the likely causes remain unclear, we intend to focus on presenting simulation results instead of offering a sound explanation of the underlying physics.

A suite of diagnostics are being proposed for use in the Juliet experiment (IER-128). In order to calibrate and test the diagnostics prior to use, the LLNL calibration facility and Godiva pulsed reactor will be used to provide intense sources of neutrons and gammas. Due to the similarities of the Godiva and Juliet radiation fields, the diagnostics being developed and tested for Juliet can also play an on-going role in diagnostics for Godiva as well as, perhaps, other critical assembly experiments. Similar work is also being conducted for IER-147 for the purpose of characterizing the Godiva radiation field in support of an upcoming international nuclear accident dosimetry exercise. Diagnostics developed and fielded under IER-147 can provide valuable data with respect to the neutron and gamma energy spectrums in the vicinity of Godiva which is relevant to the calibration of Juliet diagnostics.

In a previous paper, the composite exposure rate conversion factor (ECF) for nuclear fallout was calculated using a simple theoretical photon-transport model. The theoretical model was used to fill in the gaps in the FGR-12 table generated by ORNL. The FGR-12 table contains the individual conversion factors for approximate 1000 radionuclides. However, in order to calculate the exposure rate during the first 30 minutes following a nuclear detonation, the conversion factors for approximately 2000 radionuclides are needed. From a human-effects standpoint, it is also necessary to have the dose rate conversion factors (DCFs) for all 2000 radionuclides. The DCFs are used to predict the whole-body dose rates that would occur if a human were standing in a radiation field of known exposure rate. As calculated by ORNL, the whole-body dose rate (rem/hr) is approximately 70% of the exposure rate (R/hr) at one meter above the surface. Hence, the individual DCFs could be estimated by multiplying the individual ECFs by 0.7. Although this is a handy rule-of-thumb, a more consistent (and perhaps, more accurate) method of estimating the individual DCFs for the missing radionuclides in the FGR-12 table is to use the linear relationship between DCF and total gamma energy releasedmore » per decay. This relationship is shown in Figure 1. The DCFs for individual organs in the body can also be estimated from the estimated whole-body DCF. Using the DCFs given FGR-12, the ratio of the organ-specific DCFs to the whole-body DCF were plotted as a function of the whole-body DCF. From these plots, the asymptotic ratios were obtained (see Table 1). Using these asymptotic ratios, the organ-specific DCFs can be estimated using the estimated whole-body DCF for each of the missing radionuclides in the FGR-12 table. Although this procedure for estimating the organ-specific DCFs may over-estimate the value for some low gamma-energy emitters, having a finite value for the organ-specific DCFs in the table is probably better than having no value at all. A summary of the complete ECF and DCF values are given in Table 2.« less

As part of the proficiency training for the Radiological Mapping mission of the Aerial Measuring System (AMS), a survey team from the Remote Sensing Laboratory-Nellis (RSL-Nellis) conducted an aerial radiological survey of selected areas of the city of North Las Vegas for the purpose of mapping natural radiation background and locating any man-made radioactive sources. Survey areas were selected in collaboration with the City Manager's office and included four separate areas: (1) Las Vegas Motor Speedway (10.6 square miles); (2) North Las Vegas Downtown Area (9.2 square miles); (3) I-15 Industrial Corridor (7.4 square miles); and (4) Future site of University of Nevada Las Vegas campus (17.4 square miles). The survey was conducted in three phases: Phase 1 on December 11-12, 2007 (Areas 1 and 2), Phase 2 on February 28, 2008 (Area 3), and Phase 3 on March 19, 2008 (Area 4). The total completed survey covered a total of 44.6 square miles. The flight lines (without the turns) over the surveyed areas are presented in Figures 1, 2, 3, and 4. A total of eight 2.5-hour-long flights were performed at an altitude of 150 ft above ground level (AGL) with 300 feet of flight-line spacing. Water line andmore » test line flights were conducted over the Lake Mead and Government Wash areas to ensure quality control of the data. The data were collected by the AMS data acquisition system (REDAR V) using an array of twelve 2-inch x 4-inch x 16-inch sodium iodide (NaI) detectors flown on-board a twin-engine Bell 412 helicopter. Data, in the form of gamma energy spectra, were collected continually (every second) over the course of the survey and were geo-referenced using a differential Global Positioning System. Collection of spectral data allows the system to distinguish between ordinary fluctuations in natural background radiation levels and the signature produced by man-made radioisotopes. Spectral data can also be used to identify specific radioactive isotopes. As a courtesy service, with the approval of the U.S. Department of Energy, National Nuclear Security Administration, Nevada Site Office, RSL-Nellis is providing this summary to the office of the Mayor of the City of North Las Vegas along with the gross-count-based exposure rate and man-made count contour maps and GIS shape files in electronic format on a compact disk.« less

As part of the proficiency training for the Radiological Mapping mission of the Aerial Measuring System (AMS), a survey team from the Remote Sensing Laboratory-Nellis (RSL-Nellis) conducted an aerial radiological survey on December 11-12, 2007, with the purpose of mapping natural radiation background and locating any man-made radioactive sources. The survey covered 19.4 square miles (9.2 square miles over the downtown area of the City of North Las Vegas and 10.2 square miles over the Las Vegas Motor Speedway [LVMS]). The flight lines over the surveyed areas are presented in Figures 1 and 2. A total of four 2.5-hour-long flights were performed at an altitude of 150 ft above ground level (AGL) with 300 ft of flight line spacing. Water line and test line flights were conducted over the Lake Mead and Government Wash areas to ensure quality control of the data. The data were collected by the AMS data acquisition system-REDAR V using an array of twelve 2-inch x 4-inch x 16-inch sodium iodide (NaI) detectors flown on-board a twin-engine Bell 412 helicopter. Data in the form of gamma energy spectra were collected continually (every second) over the course of the survey and were geo-referenced using a differential Globalmore » Positioning System. Collection of spectral data allows the system to distinguish between ordinary fluctuations in natural background radiation levels and the signature produced by man-made radioisotopes sources. Spectral data can also be used to identify specific radioactive isotopes. As a courtesy service with the approval of the U.S. Department of Energy, National Nuclear Security Administration, Nevada Site Office, RSL-Nellis is providing this summary to the office of the Mayor of City of North Las Vegas and LVMS security along with the gross counts-based exposure rate and man-made counts maps.« less

Radiative strength functions (RSFs) in 93-98Mo have been extracted using the (3He,alpha gamma) and (3He,3He' gamma) reactions. The RSFs are U-shaped as function of gamma energy with a minimum at around E_gamma=3 MeV. The minimum values increase with neutron number due to the increase in the low-energy tail of the giant electric dipole resonance with nuclear deformation. The unexpected strong increase in strength below E_gamma=3 MeV, here called soft pole, is established for all 93-98Mo isotopes. The soft pole is present at all initial excitation energies in the 5-8 MeV region.

The Z-burst model and the direct propagation of UHE proton in negligible extragalactic magnetic fields produce gamma-rays afterglows and precursors halos, respectively at GeVs and TeV energy band a few degree around the UHECR arrival direction. The possible correlation of UHECR clusters (doublet, triplet) with nearby BL Lac sources at E_p = 4*10^19 eV offer a test for this necessary Gamma-UHECR trace. We estimate the secondary gamma energy and spectra and we suggest how to disentangle between the different scenarios. We show why Z-Burst model is still the most realistic model to explain UHECR behaviour and their correlation to known BL Lac sources., 8 pages, 1 Figure, Cris Conference 2004 (submitted to Nuclear Phys B)

The Waste Receiving And Processing facility (WRAP) adheres to providing gamma-ray spectroscopy instrument calibrations traceable to the National Institute for Standards and Technology (NIST) standard{sup (4)}. The detectors are used to produce quantitative results for the Waste Isolation Pilot Plant (WIPP) and must meet calibration programmatic calibration goals. Instruments must meet portions of ANSI N42.14, 1978 guide for Germanium detectors. The Non-Destructive Assay (NDA) Gamma Energy Analysis (GEA) utilizes NIST traceable line source standards for the detector system calibrations. The counting configuration is a series of drums containing the line sources and different density filler matrices. The drums are used to develop system efficiencies with respect to density. The efficiency and density correction factors are required for the processing of drummed waste materials of similar densities. The calibration verification is carried out after the calibration is deemed final, by counting a second drum of NIST traceable sources. Three in-depth calibrations have been completed on one of the two systems to date, the first being the system acceptance plan. This report has a secondary function; that being the development of the instrument calibration errors which are to be folded into the Total Instrument Uncertainty document, HNF-4050.

LLCEDATA and LLCECALC for Windows are user-friendly computer software programs that work together to determine the proper waste designation, handling, and disposition requirements for Long Length Contaminated Equipment (LLCE). LLCEDATA reads from a variety of data bases to produce an equipment data file (EDF) that represents a snapshot of both the LLCE and the tank it originates from. LLCECALC reads the EDF and a gamma assay (AV2) file that is produced by the Flexible Receiver Gamma Energy Analysis System. LLCECALC performs corrections to the AV2 file as it is being read and characterizes the LLCE. Both programs produce a variety of reports, including a characterization report and a status report. The status report documents each action taken by the user, LLCEDATA, and LLCECALC. Documentation for LLCEDATA and LLCECALC for Windows is available in three volumes. Volume 1 is a user`s manual, which is intended as a quick reference for both LLCEDATA and LLCECALC. Volume 2 is a technical manual, and Volume 3 is a software verification and validation document.

LLCEDATA and LLCECALC for Windows are user-friendly computer software programs that work together to determine the proper waste designation, handling, and disposition requirements for Long Length Contaminated Equipment (LLCE). LLCEDATA reads from a variety of data bases to produce an equipment data file(EDF) that represents a snapshot of both the LLCE and the tank from which it originates. LLCECALC reads the EDF and the gamma assay file (AV2) that is produced by the flexible Receiver Gamma Energy Analysis System. LLCECALC performs corrections to the AV2 file as it is being read and characterizes the LLCE. Both programs produce a variety of reports, including a characterization report and a status report. The status report documents each action taken by the user, LLCEDATA, and LLCECALC. Documentation for LLCEDATA and LLCECALC for Windows is available in three volumes. Volume 1 is a user`s manual, which is intended as a quick reference for both LLCEDATA and LLCECALC. Volume 2 is a technical manual, which discusses system limitations and provides recommendations to the LLCE process. Volume 3 documents LLCEDATA and LLCECALC`s verification and validation. Two of the three installation test cases, from Volume 1, are independently confirmed. Data bases used in LLCEDATA are verified andmore » referenced. Both phases of LLCECALC process gamma and characterization, are extensively tested to verify that the methodology and algorithms used are correct.« less

LLCEDATA and LLCECALC for Windows are user-friendly computer software programs that work together to determine the proper waste designation, handling, and disposition requirements for Long Length Contaminated Equipment (LLCE). LLCEDATA reads from a variety of databases to produce an equipment data file (EDF) that represents a snapshot of both the LLCE and the tank from which it originates. LLCECALC reads the EDF and the gamma assay (AV2) file that is produced by the Flexible Receiver Gamma Energy Analysis System. LLCECALC performs corrections to the AV2 file as it is being read and characterizes the LLCE Both programs produce a variety of reports, including a characterization report and a status report. The status report documents each action taken by the user, LLCEDA TA, and LLCECALC. Documentation for LLCEDA TA and LLCECALC for Windows is available in three volumes. Volume 1 is a user`s manual, which is intended as a quick reference for both LLCEDATA and LLCECALC. Volume 2 is a technical manual, which documents LLCEDATA and LLCECALCs methodology, structure, and format, provides sample calculations; discusses system limitations; and provides recommendations to the LLCE process. Volume 3 is a software verification and validation document LLCEDATA and LLCECALC for Windows are sponsored by more » the U.S.Department of Energy. They were developed and are maintained by Engineering, Waste Management Federal Services, Inc., Northwest Operations. Copies of the software and documentation are available by contacting Engineering, Waste Management Federal Services, Inc., Northwest Operations, Richland, Washington. « less

An analogy is presented between periodic persistent currents in mesoscopic rings and staggerings of gamma energy transitions from some nuclear high-spin states. Various sources of damping of the expected periodic structures in both physical systems are compared. This discussion provides, in the nuclear case, a tentative explanation of the scarcity of such staggerings, their appearance near 150Gd and the existence of a spin-window for their observation.

Sri Lanka is well known for high-quality gemstones and approximately 25% of the total land area is liable for potential gem fields. Despite of that identification of new promising gem bearing areas is essential. In Sri Lanka, such investigations are mostly based on the sedimentological and geochemical analysis rather than in-situ radioactive surveys which are common in global contest. Information derived from sporadic studies and gem miners revealed that Godakawela gem field has interesting radioactiveness. Hence, this study focuses on the presence of radioactive minerals, their distribution and the origin of the gem deposit in Godakawela gem field. The ambient gamma dose rate was measured by the plastic scintillation detector from 40 points in random walk mode and gamma energy value was recorded in the NaI scintillation detector. Results have proved that Godakawela region has high radioactiveness with respect to the average baseline value Sri Lanka. The radioactive anomaly pattern and the presence of zircon and tourmaline like associated minerals, together with the surrounded geological aspects have suggested that the radioactive minerals may have a primary origin. Further, X-ray diffractogram shows the corresponding peaks for euxenite as a radioactive mineral but to confirm recrystallization analysis with heat treatment is needed.

We report the results of a study of the peak shapes in the gamma spectra measured using several 5 x 5 x 5 mm{sup 3} cadmium zinc telluride (CZT) detectors. A simple parameterization involving a Gaussian and an exponential low energy tail describes the peak shapes sell. We present the variation of the parameters with gamma energy. This type of information is very useful in the analysis of complex gamma spectra consisting of many peaks.

This report summarizes the process test in which the airlift circulators in Tank 241-AZ-101 were shutdown. The test was successful, in that no extreme temperature excursions occurred. Only general data was obtianed through the use of a gamma energy probe.