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The Institute of Nuclear and Physical Engineering is currently developing a special laboratory, the Laboratory of Neutron Applications, where a DD type neutron generator is planned to be purchased and used for research purposes. As the equipment will be installed in a new facility, shielding materials will have to be utilized, to minimize the dose rate obtained by the personnel working with the generator as well as all workers of the faculty, who could potentially get close to the laboratory. The selection of shielding materials is complicated by the fact, that the room is situated partially underground on special pillars with limited load capacity, therefore the used shielding must be light and cheap. In this paper we are comparing the shielding performance of available light materials with the certified Neutronstop shielding blocks, based on the measurement conducted at the STU Mini Labyrinth and simulation performed in the SCALE6 system. The paper includes results of the neutron disappearance XS and the half-value-thickness of selected materials, the dose map around the Mini Labyrinth and a simple economic feasibility estimation for the Laboratory of Neutron Applications. [ABSTRACT FROM AUTHOR]

nEXO is a proposed search for neutrinoless double beta decay (0vββ) of 136Xe. The experiment is planning to utilize isotopically enriched xenon both as source and detection medium. Radon daughters produced by radon decays in the air can plate out on material surfaces during detector assembly and handling. The alpha particles they emit can interact with low-Z materials nearby and produce fast neutrons. These neutrons can in turn produce 137Xe when captured by 136Xe contained in the nEXO detector medium. The subsequent beta decay of 137Xe (Q = 4173 keV) can mimic 0vββ in nEXO. This paper describes simulation studies performed to estimate the background in nEXO produced by radon daughters. We will also discuss the allowed amounts of radon daughters on material surfaces in order to meet nEXO's stringent background requirements. [ABSTRACT FROM AUTHOR]

This paper presents the description of the preparation of aggregate irradiation experiment including the choice of sample types and preliminary numerical prediction of aggregate RIVE and damage under defined conditions for the research reactor LVR-15. Ten different samples from four countries were selected for the experimental investigation. The preliminary numerical analysis was performed for granite as the aggregate with the highest radiation-induced volumetric expansion (RIVE). Based on the prediction, the highest RIVE of 4.54 % at high-dose neutron fluence (0.585·1020 n/cm2, with energy E>10 keV) is expected. Thus, taking into account the sample size, the inner diameter of the irradiated capsule should be about 11 mm. The aggregate samples with the highest RIVE (granite) are expected to be damaged significantly even after irradiation to low-dose neutron fluence (0.208·1020 n/cm2, with energy E>10 keV) which will be captured during the post-irradiation examination. [ABSTRACT FROM AUTHOR]

The new solid state track detector analysis system for neutron dosimetry and radon measurement TASLImage™ was installed at the Slovak University of Technology, Bratislava. This paper describes the test of its performance in the measurement of neutron doses. The linearity of the response of poly allyl diglycol carbonate (PADC) detectors was tested for two regions of obtained doses, 27-378 µSv and 0.5 - 3 mSv. Results were compared to H*(10) ambient dose equivalent measured by the NuDET-ENE neutron detector. [ABSTRACT FROM AUTHOR]

The Mini Labyrinth experiment is a simple neutron and gamma shielding experiment developed at Slovak University of Technology (STU), inspired by the ALARM-CF-AIR-LAB-001 ICSBEP benchmark. Compared to the original Labyrinth, which was made from concrete blocks and had dimension of several meters, the STU Mini Labyrinth is approximately ten times smaller and consists of NEUTRONSTOP shielding blocks. So far, several versions and modifications of the Mini Labyrinth have been investigated, currently the V2-25-L version is used for code evaluation. This version uses a PuBe neutron source loaded in the entrance of the Mini Labyrinth, a plastic tank filled with light water moderator and the NuDET plastic scintillation neutron detector, which can be placed around the experimental workplace. This detector has a significant role in the experiment since it is a calibration apparatus and provides real time data on the rates of ambient dose equivalents of neutron radiation. On the other hand, as it is a certified commercial product, the response function of this detector is unknow, which makes a significant challenge of verifying the measured data with computer codes. This paper presents a result of a series of measurements with the NuDET detector performed at STU and discusses the options, how to verify the experimental results by the SCALE6 system in the most effective way. [ABSTRACT FROM AUTHOR]

The paper aims to study the quadrupole deformation and deformation energy curves of , even-even S 50 94 − 168 n isotopes (from the neutron to proton drip lines) which is one of the most interesting isotopic chains in the periodic table. The results are carried out in the framework of the Hartree-Fock-Bogoliubov (HFB) method with the HFB9 Skyrme force by using the HFBTHO code version (3.00) and compared with the available values of Finite Range Droplet Macroscopic model (FRDM), Relativistic Mean Field (RMF) theory. Sn isotopes of A<144 remain robustly spherical till N reaches 144 except for some nuclei where the deformation is quite small. Nuclei above this neutron number show an interesting change to prolate shape. Overall, An agreement is found between our calculations and other models. [ABSTRACT FROM AUTHOR]

In this paper, some nuclear features of some neutron-rich Al isotopes chain with neutron numbers N=14-22 near the island of inversion N=20 were investigated. The goal of this study was to verify the presence and magnitude of the inversion nature as the number of neutrons increases in these nuclei. For this purpose, the non-relativistic Hartree- Fock (HF) approach based on Skyrme parameterizations in two model space; sd with USDA interaction and sdpf with SDPFMU interaction was used. The results were compared with the available experimental data from NNDC and Ref. [1-3]. They support the validity of both the sd model for 28-32Al with normal ground state configuration, and sdpf model for 33&34Al with intruder ground state configuration. [ABSTRACT FROM AUTHOR]

The ITER Radial Neutron Camera (RNC) is a diagnostic system designed as a multichannel detection system to measure the uncollided neutron flux from the plasma, generated in the tokamak vacuum vessel, providing information on neutron emissivity profile. The RNC consists of array of cylindrical collimators located in two diagnostic structures: the ex-port system and the in-port system. The in-port system, contains the diamond detectors which need a temperature protection. Feasibility study of the efficiency of the cooling system for the In-port Detector Modules of the RNC during baking process was the main goal of thermo-hydraulic numerical modeling. The paper presents the concept of the cooling system layout and the original way of integration of numerical thermo-hydraulic analyses of the in-port detector cassette. Due to the large extent of the detector cassette it is impossible to include all relevant thermal and hydraulic effects in one global model with sufficient level of details. Thus the modelling strategy is based on the concept of three stage modelling from details to global model. The presented paper includes results of numerical calculations made with ANSYS Fluent software in order to provide the final answer, including calculation of heat loads in the detector cassette from adjacent walls during baking and normal operation conditions. [ABSTRACT FROM AUTHOR]

This paper presents the theoretical analysis of neutron transfer mechanism for the reaction 181Ta(18O, 19O) at energies 81.86 and 90.05 MeV in the center of mass system. Numerical solution of the time-dependent Schrödinger equation is used for studying neutron transfer processes. The evolution of the wave function for the neutron from the uppermost occupied single-particle neutron level of the 181Ta nucleus is determined. The dynamics of neutron transfer process is described and the probabilities of occupation of initially unoccupied single-particle neutron levels of the 18O nucleus are determined. [ABSTRACT FROM AUTHOR]

This paper examined the fusion of 28Si with 90,96Zr-target by opting the energy dependent Woods-Saxon potential (EDWSP) model and code CCFULL. The CCFULL analysis suggested that for 28Si + 90Zr system, the vibrational excitations of 90Zr-isotope have been found to be very important while for 28Si + 96Zr system, in addition to multiphoton vibrational states of target, the considerations of nucleon transfer are essentially needed for the adequate addressal of the observed fusion data. In contrast, predictions based on EDWSP model appropriately recovered the fusion data of 28Si + 90,96Zr systems at sub-barrier realm. The EDWSP based results do not include various channel coupling effects explicitly but being the energy dependent nature of Woods-Saxon potential (WSP), the calculational results intrinsically incorporate the nuclear effects of the fusing systems. This unambiguously clarified that the energy dependent nature of the EDWSP generates analogous barrier modulations as emerged from the CCFULL analysis. [ABSTRACT FROM AUTHOR]

Cement based composites are considered to be a very important part of the present multi-barrier concepts in nuclear waste management. To assess their suitability in this respect, it is necessary to understand in detail the transport of radionuclides in such composites. One of the tasks is a proper description of adsorption into the pore walls. Usually, an equilibrium isotherm is assumed to well describe the sorption. However, in this paper we introduce a first-order kinetic sorption model to show that it could plausibly interpret experimental data on the transport of gadolinium in a dry cement composite. The data are measured by neutron imaging, and the optimization of model parameters in order to fit the data is based on the Levenberg-Marquardt method. [ABSTRACT FROM AUTHOR]

In the present paper, we have theoretically calculated the nuclear neutron and proton densities, initial exciton numbers and binding energies of the Strontium isotopes (84-96Sr). The Skyrme Hartree Fock (SHF) parameterizations S2, S3, SG2, SKa, SKM, SKM*, and T3 are used in the neutron and proton density calculations. The initial neutron and proton exciton numbers of the 84-96Sr isotopes have been calculated using the SKM* Skyrme parameter. The obtained results from Skyrme force parameters are discussed and compared with each other's and are shown to be in agreement with each other. [ABSTRACT FROM AUTHOR]

The uncertainty in neutron cross section values strongly depends on the quality and characteristics of the deposited actinide films which are used as “targets” in the nuclear experiments. Until recently, at the Joint Research Centre in Geel (JRC-Geel), mass and areal densities of actinide layers were determined by measuring activity (using alpha-particle counting), isotopic composition (using thermal ionisation mass spectrometry) and diameter. In this study a series of 238U deposits, prepared by molecular plating and vacuum deposition on different substrates, were characterized with additional non-destructive and destructive analysis techniques. The quality of the deposits was investigated by autoradiography, high-resolution alpha-particle spectrometry, and scanning electron microscopy. The elemental composition was determined by x-ray photoelectron spectroscopy and inductively coupled plasma mass spectrometry. The latter technique was also applied on the U3O8 starting material and the converted UF4 powder. This paper compares the quality and morphology of deposited 238U films prepared by molecular plating and vacuum deposition on various backings, including their elemental composition determined by different characterization techniques. Also discussed are problems in target preparation and characterization. [ABSTRACT FROM AUTHOR]

Measurement of neutron cross section data is a core activity of the JRC-Directorate G for Nuclear Safety and Security in Geel. After a period of reduced activity and in line with a renewed interest for nuclear data required for GenIV reactors and waste minimization, the demand for high quality actinide targets increased. Physical vapour deposition by thermal evaporation is a key technique to prepare homogeneous thin actinide layers, but due to ageing effects the earlier in-house developed equipment can no longer provide the required quality. Because of a current lack of experience and human resources cooperation with private companies is required for the development of new deposition equipment directly integrated in a glove box. In this paper we describe the design, implementation and validation of the first commercial actinide evaporator in a glove box as well as the optimization of the deposition process. Highly enriched 238U3O8 was converted to 238UF4 powder and several deposition runs were performed on different substrates. The deposition parameters were varied and defined in order to guarantee physical and chemical stable homogeneous UF4 layers, even on polished substrates which was not longer feasible with the older equipment. The stability problem is discussed in view of the thin layer growth by physical vapour deposition and the influence of the deposition parameters on the layer quality. The deposits were characterized for the total mass by means of substitution weighing and for the areal density of 238U by means of alpha particle counting and thermal ionization mass spectrometry (TIMS). The quality of the layer was visually evaluated and by means of stereo microscopy and auto radiography. [ABSTRACT FROM AUTHOR]

The present paper contains investigations of the creep process in the cobalt-based amorphous metallic alloy within the temperature range from 300 up to 1023 K. In all the curves of deformation there were observed jumps and dying oscillations. It is noted that the creep of the sample ribbons is unstable and results in the thinning of ribbons with tightening and crimping. There is suggested the mechanism of inhomogeneous deformation, which takes place in course of the process of creep under intermittent heating. For the evaluation of amorphism in the treated samples there have been carried out neutron-graphical and X-ray diffraction investigations, as well as thermal analysis. [ABSTRACT FROM AUTHOR]

Attempts to explain the origin of r-process elements in our Solar System (S.S.) still face entwined uncertainties, stemming from the extrapolation of nuclear structure from the line of β-stability to the neutron drip line, inconsistent sources of different properties (e.g. nuclear masses and β-decay quantities), and the poor understanding of astrophysical conditions, which are often hard to disentangle. In this paper, we will focus on the two interrelated gross β-decay quantities T1/2 and Pn. We compare the recent experimental T1/2 of very neutron-rich isotopes in the 36Kr to 50Sn region (measured at RIKEN) with consistent QRPA(GT+ff) predictions based on the two global deformed mass models ETFSI-Q(1996) and FRDM(2012). Analyzing the observed agreement and remaining deficiencies of the T1/2 trends, we predict the still unknown β-delayed neutron-emission probabilities (Pn) for these isotopes using the empirical Kratz-Herrmann formula (KHF) and the microscopic ETFSI-Q/QRPA(GT+ff) model combination. [ABSTRACT FROM AUTHOR]

This paper summarizes a Photomultiplier-Scintillator diagnostic system for use in our plasma focus experiments at the Center for Plasma Research INTI IU. The system features an anode-grounded high pulse linearity voltage divider and uses NE102A plastic scintillators. It has detected D-D neutrons in INTI plasma focus device with clear and high signal to noise ratio. Neutron TOF of 120 ns has been measured from the time difference between hard x-ray pulse peak and neutron peak time over a flight path of 2.6±0.01 m; giving energy of 2.5±0.1 MeV for these side-on neutrons. [ABSTRACT FROM AUTHOR]

In this paper, we use Lee's 5 phase model code to configure both the India Bhabha Atomic Research Center (BARC) Plasma focus machine operating in the pressure (P0) range from 1 Torr to 14 Torr as well as the Imperial College Plasma Focus Machine operating in the pressure (P0) range from 0.5 Torr to 6 Torr to compare the computational neutron yield to the experimental neutron yield as well as to obtain the relationship between axial speed va, radial shock speed vs, piston speed vp and pinch temperature with P0 for these machines. [ABSTRACT FROM AUTHOR]

The radiation resulting from neutron interactions with Ge nuclei in active volume of HPGe detectors is one of the main concerns in low-level gamma spectroscopy measurements [1,2]. It is usually not possible to measure directly spectrum of neutrons which strike detector. This paper explore the possibility of estimation of neutron spectrum using measured activities of certain Ge(n,γ) and Ge(n,n') reactions (obtained from low-level gamma measurements), available ENDF cross section data and unfolding procedures. In this work HPGe detector with passive shield made from commercial low background lead was used for the measurement. The most important objective of this study was to reconstruct muon induced neutron spectrum created in the shield of the HPGe detector. MAXED [3] and GRAVEL [4] algorithms for neutron spectra unfolding were used. The results of those two algorithms were compared and we analyzed the sensitivity of the unfolding procedure to the various input parameters. [ABSTRACT FROM AUTHOR]

Current generation light water reactors (LWRs), sodium cooled fast reactors (SFRs), small modular reactors (SMRs), and next generation nuclear plants (NGNPs) produce harsh environments in and near the reactor core that can severely tax material performance and limit component operational life. To address this issue, several Department of Energy Office of Nuclear Energy (DOE-NE) research programs are evaluating the long duration irradiation performance of fuel and structural materials used in existing and new reactors. In order to maximize the amount of information obtained from Material Testing Reactor (MTR) irradiations, DOE is also funding development of enhanced instrumentation that will be able to obtain in-situ, real-time data on key material characteristics and properties, with unprecedented accuracy and resolution. Such data are required to validate new multi-scale, multi-physics modeling tools under development as part of a science-based, engineering driven approach to reactor development. It is not feasible to obtain high resolution/microscale data with the current state of instrumentation technology. However, ultrasound-based sensors offer the ability to obtain such data if it is demonstrated that these sensors and their associated transducers are resistant to high neutron flux, high gamma radiation, and high temperature. To address this need, the Advanced Test Reactor National Scientific User Facility (ATRNSUF) is funding an irradiation, led by PSU, at the Massachusetts Institute of Technology Research Reactor to test the survivability of ultrasound transducers. As part of this effort, PSU and collaborators have designed, fabricated, and provided piezoelectric and magnetostrictive transducers that are optimized to perform in harsh, high flux, environments. Four piezoelectric transducers were fabricated with either aluminum nitride, zinc oxide, or bismuth titanate as the active element that were coupled to either Kovar or aluminum waveguides and two magnetostrictive transducers were fabricated with Remendur or Galfenol as the active elements. Pulse-echo ultrasonic measurements of these transducers are made insitu. This paper will present an overview of the test design including selection criteria for candidate materials and optimization of test assembly parameters, data obtained from both out-of-pile and in-pile testing at elevated temperatures, and an assessment based on initial data of the expected performance of ultrasonic devices in irradiation conditions. [ABSTRACT FROM AUTHOR]

Initially, yields (or abundances) and branching ratios of β-delayed neutrons (βdn) from fission products (Pn-values) have had their main importance in nuclear reactor control. At that time, the six-group mathematical approximation of the time-dependence of βdn-data in terms of the so-called "Keepin groups" was generally accepted. Later, with the development of high-resolution neutron spectroscopy, ßdn data have provided important information on nuclear-structure properties at intermediate excitation energy in nuclei far from stability, as well as in nuclear astrophysics. In this paper, I will present some examples of the βdn-studies performed by the Kernchemie Mainz group during the past three decades. This work has been recognized as an example of "broad scientific diversity" which has led to my nomination for the 2014 Hans A. Bethe prize. [ABSTRACT FROM AUTHOR]

The deuterium Dense Plasma Focus (DPF) can produce copious amounts of MeV neutrons and can be used as an efficient neutron source. However, the mechanism by which neutrons are produced within the DPF is poorly understood and this limits our ability to optimize the device. In this paper we present results from a computational study aimed at understanding how neutron production occurs in DPFs with a current between 70 kA and 500 kA and which parameters can affect it. A combination of MHD and kinetic tools are used to model the different stages of the DPF implosion. It is shown that the anode shape can significantly affect the structure of the imploding plasma and that instabilities in the implosion lead to the generation of large electric fields at stagnation. These electric fields can accelerate deuterium ions within the stagnating plasma to large (>100 keV) energies leading to reactions with ions in the cold dense plasma. It is shown that the electromagnetic fields present can significantly affect the trajectories of the accelerated ions and the resulting neutron production. [ABSTRACT FROM AUTHOR]

A study of asymmetric fission yield behavior from a neutron-deficient Hg isotope has been conducted. The fission yield calculation of the neutron-deficient Hg isotope using Brownian Metropolis shape had showed unusual result at decreasing energy. In this paper, this interesting feature will be validated by using nine degree of scission shapes parameterization from Brosa model that had been implemented in TALYS nuclear reaction code. This validation is intended to show agreement between both model and the experiment result. The expected result from these models considered to be different due to dynamical properties that implemented in both models. [ABSTRACT FROM AUTHOR]

The Mega Ampere Spherical Tokamak Upgrade (MAST Upgrade) is intended as a demonstration of the physics viability of the Spherical Tokamak (ST) concept and as a platform for contributing to ITER/DEMO physics. Concerning physics exploitation, MAST Upgrade plasma scenarios can contribute to the ITER Tokamak physics particularly in the field of fast particle behavior and current drive studies. At present, MAST is equipped with a prototype neutron camera (NC). On the basis of the experience and results from previous experimental campaigns using the NC, the conceptual design of a neutron camera upgrade (NC Upgrade) is being developed. As part of the MAST Upgrade, the NC Upgrade is considered a high priority diagnostic since it would allow studies in the field of fast ions and current drive with good temporal and spatial resolution. In this paper, we explore an optional design with the camera array viewing the poloidal section of the plasma from different directions. [ABSTRACT FROM AUTHOR]

The diagnostic systems of DEMO that are mounted on or near the torus, whether intended for the monitoring and control functions of the engineering aspects or the physics behaviour of the machine, will have to be designed to suit the hostile nuclear environment. This will be necessary not just for their survival and correct functioning but also to satisfy the pertinent regulatory bodies, especially where any of them relate to machine protection or the prevention or mitigation of accidents foreseen in the safety case. This paper aims to indicate the more important of the reactor design considerations that are likely to apply to diagnostics for DEMO, drawn from experience on JET, the provisions in hand for ITER and modelling results for the wall erosion and neutron damage effects in DEMO. [ABSTRACT FROM AUTHOR]

Neutrons and radon are both ubiquitous in the earth's crust. The neutrons of terrestrial origin are strongly related to radon since they originate mainly from the interactions between the alpha particles from the decays of radioactive-gas (namely Radon and Thoron) and the light nuclei. Since the early studies in the field of neutrons, the radon gas was used to produce neutrons by (a, n) reactions in beryllium. Another important similarity between radon and neutrons is that they can be detected only through the radiations produced respectively by decays or by nuclear reactions. These charged particles from the two distinct nuclear processes are often the same (namely alpha-particles). A typical neutron detector is based on a radiator facing a alpha-particle detector, such as in the case of a neutron film badge. Based on the similarity between neutrons and radon, a film badge for radon has been recently proposed. The radon film badge, in addition to be similar, may be even identical to the neutron film badge. For these reasons, neutron measurements can be easily affected by the presence of unpredictable large radon concentration. In several cold fusion experiments, the CR-39 plastic films (typically used in radon and neutron film-badges), have been the detectors of choice for measuring neutrons. In this paper, attempts will be made to prove that most of these neutron-measurements might have been affected by the presence of large radon concentrations. [ABSTRACT FROM AUTHOR]

The European Spallation Source (ESS), Lund, Sweden will be a 5MW long-pulse neutron spallation research facility and will enable new opportunities for researchers in the fields of life sciences, energy, environmental technology, cultural heritage and fundamental physics. Neutrons are produced by accelerating a high-energy proton beam into a rotating helium-cooled tungsten target. These neutrons pass through moderators to reduce their energy to an appropriate range (< 5 meV for cold neutrons); two of which will use liquid hydrogen at 17 K as the moderating and cooling medium. There are several technical challenges to overcome in the design of a robust system that will operate under such conditions, not least the 20 kW of deposited heat. These challenges and the associated design solutions will be detailed in this paper. [ABSTRACT FROM AUTHOR]

The European Spallation Source (ESS) is a neutron science facility funded by a collaboration of 17 European countries currently under design and construction in Lund, Sweden. The centerpiece of ESS is a 2.5 GeV proton linac utilizing superconducting RF cavities operating at 2 K. In addition to cooling the SRF cavities, cryogenics is also used at ESS in the liquid hydrogen moderators surrounding the target. ESS also uses both liquid helium and liquid nitrogen in a number of the planned neutron instruments. There is also a significant cryogenic installation associated with the site acceptance testing of the ESS cryomodules. The ESS cryogenic system consists of 3 separate helium refrigeration/liquefaction plants supplying the accelerator, target moderators and instruments. An extensive cryogenic distribution system connects the accelerator cryoplant with the cryomodules. This paper describes the preliminary design of the ESS cryogenic system including the expected heat loads. Challenges associated with the required high reliability and turn-down capability will also be discussed. A unique feature of ESS is its commitment to sustainability and energy recovery. A conceptual design for recovering waste heat from the helium compressors for use in the Lund district heating system will also be described. [ABSTRACT FROM AUTHOR]

In dark matter WIMP searches the neutron shielding plays a crucial role in attenuating neutron flux and hence, suppressing nuclear recoil event rate - one of the key background mimicking WIMP interactions. The transition from EDELWEISS-II to EDELWEISS-III with 40 detectors with increased mass and improved background rejection has required the modification of the neutron shielding. In this paper we describe the new neutron shielding design and give an estimate of the expected neutron rate in comparison with the previous stage of the experiment. [ABSTRACT FROM AUTHOR]

Rejection and protection from background is a key issue for the next generation SuperCDMS SNOLAB experiment that will have a cross-section sensitivity of better than 8 × 10-46 cm2 for spin-independent WIMP-nucleon interactions. This paper presents the details of the methods used to reject electromagnetic backgrounds using the new iZIP detectors that are currently operated in the Soudan Underground Laboratory, MN and the methods the collaboration is investigating to protect against neutron background in the next generation SuperCDMS experiment. [ABSTRACT FROM AUTHOR]

In this paper, we shall present a simple VME front-end system that employs the FADC CAEN V1720 8- channel 12-bit 250-MS/s digitizer. This system produces coincidence spectra between the trigger particle and other detectors and it replaces the traditional technique of chaining analog electronics. Tests have been performed using a pulser working at different frequencies as well as employing a 252Cf source in concert with an array of detectors. [ABSTRACT FROM AUTHOR]

One of the most critical parameters in activation analysis is the flux density of the activating radiation, its spatial distribution in particular. The validity of the basic equation for calculating the activity induced to the exposed item depends upon the fulfilment of several conditions, the most relevant of them being equal doses of incident activating radiation received by the unknown sample, the calibration material and the reference material, respectively. This requirement is most problematic if accelerator-produced radiation is used for activation. Whilst nuclear research reactors usually are equipped with exposure positions that provide fairly homogenous activation fields for thermal neutron activation analysis accelerator-generated particle beams (neutrons, photons, charged particles) usually exhibit axial and, in particular, sharp radial flux gradients. Different experimental procedures have been developed to fulfil the condition mentioned above. In this paper, three variants of the application of flux monitors in photon activation analysis are discussed (external monitor, additive and inherent internal monitor). Experiments have indicated that the latter technique yields highest quality of the analytical results. [ABSTRACT FROM AUTHOR]

Diamond is perhaps the most versatile, efficient and radiation tolerant material available for use in beam detectors with a correspondingly wide range of applications in beam instrumentation. Numerous practical applications have demonstrated and exploited the sensitivity of diamond to charged particles, photons and neutrons. In this paper, a brief description of a generic diamond detector is given and the interaction of the CVD diamond detector material with protons, electrons, photons and neutrons is presented. Latest results of the interaction of sCVD diamond with 14 MeV mono-energetic neutrons are shown. [ABSTRACT FROM AUTHOR]

Elemental characterization of low Z elements (C,H,Cl,Fe) inside bulk materials were performed using PGNAA technique. Samples having elemental composition similar to explosives were used for such experimentations using moderated DD neutrons as well as DT(14MeV) neutrons. We could observe characteristic prompt capture gamma rays of hydrogen (2.224MeV), nitrogen (10.83 MeV), chlorine (6.11 MeV) and Fe (6.02MeV and 7.63MeV) also (n,n'γ) prompt gamma signal (4.43MeV) of carbon. BGO detector has been used for gamma spectrum acquisition. These experimentations has been carried out for initial feasibility studies of detecting prompt gamma lines as a part of PGNAA technique based explosive detection system development. A detail description of experimental set up and procedure has been discussed in paper. [ABSTRACT FROM AUTHOR]

This paper describes the performance of the SNS H- ion source and LEBT as they continue to deliver ∼50 mA H- beams at a 5.3% duty factor required for neutron production with a ∼1MW proton beam since the fall of 2009. The source continues to deliver persistent H- beams for up to 6 weeks without adding Cs after an initial dose of ∼4 mg, except when there are excessive plasma impurities. In one case the H- beam decayed due to an air leak, which is shown to be consistent with sputtering of the Cs layer, and which allows us to bracket the plasma potential. In another case, the performance of two sources degraded progressively, which appears to be consistent with a progressive deterioration of the Cs covered Mo converter. These two and other recently discovered issues are discussed in detail. [ABSTRACT FROM AUTHOR]

In this paper, a series of neutronics analysis of hybrid power reactor is proposed. The ideas of loading different fuels in a modular-type fission blanket is analyzed, fitting different level of fusion developments, i.e., the current experimental power output, the level can be obtained in the coming future and the high-power fusion reactor like ITER. The energy multiplication of fission blankets and tritium breeding ratio are evaluated as the criterion of design. The analysis is implemented based on the D-type simplified model, aiming to find a feasible 1000MWe hybrid power reactor for 5 years' lifetime. Three patterns are analyzed: 1) for the low fusion power, the reprocessed fuel is chosen. The fuel with high plutonium content is loaded to achieve large energy multiplication. 2) For the middle fusion power, the spent fuel from PWRs can be used to realize about 30 times energy multiplication. 3) For the high fusion power, the natural uranium can be directly used and about 10 times energy multiplication can be achieved. [ABSTRACT FROM AUTHOR]

The paper reviews the characteristic features of a volumetric neutron source based on the gas dynamic trap and the results of current experiments at GDT device on modeling of the operational regimes of the neutron source. Some limiting factors in the current experiments and possible next steps towards more comprehensive modeling in a future experimental device are discussed. [ABSTRACT FROM AUTHOR]

The ITER cryogenic system will have to cope with substantial dynamic heat loads due to the magnetic field variation and the production of neutrons generated by the fusion reactions. This will induce large pressure variations in the primary cooling loop of the superconducting coils, which results in the large power variation to the helium refrigerator. The HELIOS test facility, developed at CEA-Grenoble, and initially designed to study the pulse mitigation of the JT-60SA central solenoid cooling circuit (in order to smooth the pulsed load and test components), was adapted to the ITER cooling loop requirements. This paper presents the experimental results concerning the specific ITER analysis. We reproduce experimentally the pressure variation of the Central Solenoid (CS) loop predicted by a numerical model, and observe the behaviour of the circulating pump in these conditions. The investigations of the heat load smoothing methods, using the circuit of Toroidal Field Structures, such as the pulse mitigation by temporary by-pass of the flow of the Structure cooling loop, and variation of the speed of the cold circulating pump, are also presented. [ABSTRACT FROM AUTHOR]

Japan, a non-nuclear weapons state, has established a commercial nuclear fuel cycle including LWRs, and now is developing a fast neutron reactor fuel cycle as part of the next generation nuclear energy system, with commercial operation targeted for 2050. Japan Atomic Energy Agency (JAEA) is the independent administrative agency for conducting comprehensive nuclear R&D in Japan after the merger of Japan Atomic Energy Research Institute (JAERI) and Japan Nuclear Cycle Development Institute (JNC). JAEA and its predecessors have extensive experience in R&D, facility operations, and safeguards development and implementation for new types of nuclear facilities for the peaceful use of nuclear energy. As the operator of various nuclear fuel cycle facilities and numerous nuclear materials, JAEA makes international contributions to strengthen nuclear non-proliferation. This paper provides an overview of JAEA's development of nuclear non-proliferation and safeguards technologies, including remote monitoring of nuclear facilities, environmental sample analysis methods and new efforts since the 2010 Nuclear Security Summit in Washington D.C. [ABSTRACT FROM AUTHOR]

The study of collisions around the Coulomb barrier induced by halo and/or weakly bound nuclei has been the object of many publications in the last years. In this paper we will summarize some recent results on the above topic obtained by our group at INFN-LNS Catania. Results concerning collisions induced by the neutron halo nuclei 11Be and 6He on a 64Zn target will be presented and compared with the ones for collisions induced by the stable isotopes 9,10Be and 4He on the same target. Results concerning the study of elastic scattering and fusion reactions in collisions induced by the stable weakly bound nuclei 6,7Li on the same 64Zn target will also be presented and discussed. [ABSTRACT FROM AUTHOR]

Particle radiotherapy facilities are highly capital intensive and must operate over decades to recoup the original investment. We describe the successful, long-term operation of a neutron radiotherapy center at the University of Washington, which has been operating continuously since September 1984. To date, 2836 patients have received neutron radiotherapy. The mission of the facility has also evolved to include the production of unique radioisotopes that cannot be made with the low-energy cyclotrons more commonly found in nuclear medicine departments. The facility is also used for neutron damage testing for industrial devices. In this paper, we describe the challenges of operating such a facility over an extended time period, including a planned maintenance and upgrade program serving diverse user groups, and summarize the major clinical results in terms of tumor control and normal tissue toxicity. Over time, the mix of patients being treated has shifted from common tumors such as prostate cancer, lung cancer, and squamous cell tumors of the head and neck to the rarer tumors such as salivary gland tumors and sarcomas due to the results of clinical trials. Current indications for neutron radiotherapy are described and neutron tolerance doses for a range of normal tissues presented. [ABSTRACT FROM AUTHOR]

Delayed neutron (DN) and delayed photon (DP) emissions from photofission reactions play an important role for applications involving nuclear material detection and characterization. To provide new, accurate, basic nuclear data for evaluations and data libraries, an experimental programme of DN and DP measurements has been undertaken for actinides with bremsstrahlung endpoint energy in the giant resonance region (∼15 MeV). In this paper, the experimental setup and the data analysis method will be described. Experimental results for DN and DP characteristics will be presented for 232Th, 235,238U, 237Np, and 239Pu. Finally, an example of an application to study the contents of nuclear waste packages will be briefly discussed. [ABSTRACT FROM AUTHOR]

Many applications of neutrons for non-invasive measurements began with isotopic sources such as AmBe or Cf-252. Political factors have rendered AmBe undesirable in the United States and other countries, and the supply of Cf-252 is limited and significantly increasing in price every few years. Compact and low-power deuterium-tritium (DT) electronic neutron generators can often provide sufficient flux, but the 14-MeV neutron spectrum is much more energetic (harder) than an isotopic neutron source. A series of MCNP simulations was run to examine the extent to which the 14-MeV DT neutron spectrum could be softened through the use of high-Z and low-Z materials. Some potential concepts of operation require a portable neutron generator system, so the additional weight of extra materials is also a trade-off parameter. Using a reference distance of 30 cm from the source, the average neutron energy can be lowered to be less than that of either AmBe or Cf-252, while obtaining an increase in flux at the reference distance compared to a bare neutron generator. This paper discusses the types and amounts of materials used, the resulting neutron spectra, neutron flux levels, and associated photon production. [ABSTRACT FROM AUTHOR]

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory reached 1-MW of beam power in September 2009, and now routinely operates near 1-MW for the production of neutrons. This paper reviews the performance, operational issues, implemented and planned mitigations of the SNS H- ion source to support such high power-level beams with high availability. Some results from R&D activities are also briefly described. [ABSTRACT FROM AUTHOR]

This paper highlights the issues which need to be addressed in undertaking accurate calculations of multi-electron atoms and ions, particularly at or near the neutral end of an isoelectronic sequence. We illustrate the processes through two calculations-of transitions in Cl I and Sn II-and discuss the convergence of our results as well as updating previous work. In particular, in the case of Cl I, we propose new identifications of the levels involved in certain transitions which are important in determining the abundance of chlorine in the inter-stellar medium (ISM), while in singly ionised tin, our calculations suggest a re-evaluation of the the abundance of tin in the ISM. We also confirm recent identification of Sn II lines seen in tokamak plasmas. [ABSTRACT FROM AUTHOR]

The paper presents an overview of electronic personal dosemeters for neutrons in mixed neutron/photon fields. The energy response of commercially available electronic dosemeters in quasi-monoenergetic neutron fields and their performance in working places is discussed. The response curves are extended to high-energy neutrons up to 100 MeV, new prototype dosemeters are described and discussed especially for use at high-energy accelerators and in space. [ABSTRACT FROM AUTHOR]

In this paper I will illustrate examples of progress in the five main avenues of nucleon structure research in Hall B at JLab: elastic and resonance transition form factors, polarized inelastic scattering, semi-inclusive meson electroproduction, hard exclusive reactions and non-strange baryon spectroscopy. The 12 GeV machine and detector upgrade will offer an unprecedented opportunity to study all these topics in a broader kinematic domain. [ABSTRACT FROM AUTHOR]

This paper reviews exact analytical results on diffraction in time for tunneling of a particle through an arbitrary potential of finite range. It emphasizes the essential role played by the formalism of resonant states to derive the analytical solution to the time-dependent Schrödinger equation as an initial value problem and in the analysis of the corresponding transient behavior. [ABSTRACT FROM AUTHOR]

Do not replace the word “abstract,” but do replace the rest of this text. Text should remain 10-pt. If you must insert a hard line break, please use Shift+Enter rather than just tapping your “Enter” key. You may want to print this page and refer to it as a style sample before you begin working on your paper. For an experimentalist in high energy physics, the most interesting experiments that one should pursue is often well known. The very rare CP violating decay of the kaon into a pion and two neutrinos (both the charged and neutral modes) is such an experiment. We have recently proposed the charged kaon experiment to Fermilab as proposal P966. We present her a general overview of that proposal. The goal is to obtain of order 1000 events in order to confront the expected theoretical calculations and to search for physics beyond the standard model. [ABSTRACT FROM AUTHOR]

Nowadays in Russia and abroad there are several groups of scientists, engaged in development of systems based on "tagged" neutron method (API method) and intended for detection of dangerous materials, including high explosives (HE). Particular attention is paid to possibility of detection of dangerous objects inside a sea cargo container. Energy gamma-spectrum, registered from object under inspection is used for determination of oxygen/carbon and nitrogen/carbon chemical ratios, according to which dangerous object is distinguished from not dangerous one. Material of filled container, however, gives rise to additional effects of rescattering and moderation of 14 MeV primary neutrons of generator, attenuation of secondary gamma-radiation from reactions of inelastic neutron scattering on objects under inspection. These effects lead to distortion of energy gamma-response from examined object and therefore prevent correct recognition of chemical ratios. These difficulties are taken into account in analytical method, presented in the paper. Method has been validated against experimental data, obtained by the system for HE detection in sea cargo, based on API method and developed in VNIIA. Influence of shielding materials on results of HE detection and identification is considered. Wood and iron were used as shielding materials. Results of method application for analysis of experimental data on HE simulator measurement (tetryl, trotyl, hexogen) are presented. [ABSTRACT FROM AUTHOR]