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Neutrons are widely used in national defense, security, and medical health fields. It is critical to realize neutron detection with high efficiency. The most popular neutron detection scintillators such as lithium glass and 6LiF/ZnS:Ag screen exhibit insurmountable limitations: the former usually has relatively rather low light yield and latter is opaque. In this research, we report the successful construction of the novel full inorganic composite scintillators by low temperature co‐firing technology. The composite scintillator is derived from the ZnS:Ag and borate glass matrix, and it shows better transparency compared with the standard 6LiF/ZnS:Ag screen. It exhibits excellent scintillation properties with the X‐ray induced emission intensity of these composite scintillators reaching approximately 2.46 times of the standard Bi4Ge3O12 (BGO) crystal. The light output under thermal neutron excitation can reach 75 000 photons/neutron. In addition, it presents excellent neutron detection performance with natural abundance of 10B isotope. Our research findings can serve as a valuable reference for the advancement of robust neutron detection materials, particularly in the domain of ZnS:Ag‐based full inorganic scintillator for neutron detection. [ABSTRACT FROM AUTHOR]

The technological aspects of the light inorganic crystalline compounds suitable to create scintillation materials to detect charged particles and neutrons in a wide energy range have been examined. Among them, Li2CaSiO4:Eu was found to be a prospective candidate to control the valent state of the Rare Earth (RE) and to provide a high intensity of luminescence. It was demonstrated that the material has room for future improvement; however, this requires precise engineering of its composition—an experimental search of compositions or additives that will provide the maximum Eu2+/Eu3+ ratio to achieve a high scintillation light yield. The benefits of light inorganic materials are disclosed through the modeling of the linear density of nonequilibrium carriers along secondary particle tracks created in scintillators utilized for neutron detection. It is shown that oxide matrices have a larger linear density in comparison with halide crystalline compounds under alpha-particles and tritons, whereas light oxides can provide smaller numbers under protons. [ABSTRACT FROM AUTHOR]

The high energy neutron generation facilities worldwide uses the Li(p,n) system for production of the quasi mono-energetic neutrons from epithermal to few hundreds of MeV. Among the facilities either self-standing thick Li target or Li foil supported on a target assembly is used. In case of a supported Li target, either low or high mass supporting substrates like Al, C, Au, Ta etc. can be used. However, the neutron emission from the supporting substrate can interfere with the Li(p,n) reaction neutrons. In the present study neutron yields from a thin natural Li target supported on the thick natural Ta (high Z) and C (low Z) targets were measured at incident proton energies between 8-20 MeV. The proton irradiation of targets were performed at the Pelletron accelerator Facility, Mumbai and the emitted neutrons were measures at both forward (0°) and lateral (90°) directions with respect to the incident beam. The neutron yield was estimated using the CR-39 detectors and dual scintillator based active neutron spectrometer. A neutron dose equivalent (NDE) meter was also used to measure the neutron ambient dose equivalent at the measurement point. Experimentally measured neutron yields and ambient neutron dose equivalent estimates indicated higher Li(p,n) neutron yield with carbon as the supporting substrate. This is due to fewer self-emissions from natC compared to natTa target. Carbon supporting substrate also ensures improved spectral features of the Li(p,n) emission neutrons and lesser neutron fluence around the source location. This ensures efficient implementation of radiation protection practices with carbon target due to lower neutron fluence around the source compared to tantalum target. Carbon is a favorable supporting substrate compared to high Z-metal targets like Ta for emission neutron studies on Li target at proton energies between 8-20 MeV. [ABSTRACT FROM AUTHOR]

At the 5.5 MV Tandem T11/25 Accelerator Laboratory of NCSR "Demokritos" quasi-monoenergetic neutron beams can be produced in the energy ranges ∼15–21 MeV by means of the 3H(d,n)4He reaction, ∼4–11 MeV via the 2H(d,n)3He reaction, ∼2.0–5.3 MeV using the 3H(p,n)3He reaction and ∼120–650 keV via the 7Li(p,n)7Be reaction. The maximum flux has been determined to be of the order of 10 5 – 10 6 n/cm 2 s , implementing reference reactions, while the flux variation of the neutron beam is monitored using a BF3 detector and a BC501A scintillator. The neutron beams have been characterized using the multiple foil activation technique as well as extensive simulations and have been used for cross section measurements of neutron induced reactions implementing again the activation technique. [ABSTRACT FROM AUTHOR]

The paper considers and compares methods for obtaining spectra of fast neutrons using detectors based on a diamond sensor, an organic (plastic) scintillator for separating neutrons and γ-quants, and a spectrometric set of threshold activation detectors. The neutron spectrum was unfolded using the methods of least squares, Tikhonov regularization, neural networks, and maximum entropy, implemented in the MAXED code, as well as the GRAVEL iterative algorithm. In order to form detector response matrices, mathematical simulation methods and analytical calculations were used followed by verification using experimental data. The unfolding quality criteria, according to which the best method is selected, are given. [ABSTRACT FROM AUTHOR]

High-resolution neutron radiography provides novel and stirring opportunities to investigate the structures of light elements encased by heavy elements. For this study, a series of Gd2O2S:Tb, F particles were prepared using a high-temperature solid phase method and then used as a scintillation screen. Upon reaching 293 nm excitation, a bright green emission originated from the Tb3+ luminescence center. The level of F doping affected the fluorescence intensity. When the F doping level was 8 mol%, the fluorescence intensity was at its highest. The absolute quantum yield of the synthesized particles reached as high as 77.21%. Gd2O2S:Tb, F particles were applied to the scintillation screen, showing a resolution on the neutron radiograph as high as 12 μm. These results suggest that the highly efficient Gd2O2S:Tb, F particles are promising scintillators for the purposes of cold neutron radiography. [ABSTRACT FROM AUTHOR]

A neutron detector with a micro-structured boron cathode and a glass gas electron multiplier (GEM) has been developed for time-of-flight Bragg edge neutron transmission imaging. The detector has a field of view of 100 x 100 mm² and 128 x 128 pixels (pixel size 0.8 x 0.8 mm²). The neutron imaging performance of the detector was evaluated at a compact electron accelerator-driven neutron source (AISTANS). By comparison with a Li-glass detector, we found that our detector has a detection efficiency of 5% for 4 Å neutrons. In addition, a preliminary time-of-flight neutron imaging test was performed to observe the difference between the face-centered and body-centered cubic crystal structures, from which we confirmed that our detector has sufficient stability and time resolution for use in Bragg edge imaging analysis. [ABSTRACT FROM AUTHOR]

In recent years, proton therapy has gained importance as a cancer treatment modality due to its conformality with the tumor and the sparing of healthy tissue. However, in the interaction of the protons with the beam line elements and patient tissues, potentially harmful secondary neutrons are always generated. To ensure that this neutron dose is as low as possible, treatment plans could be created to also account for and minimize the neutron dose. To monitor such a treatment plan, a compact, easy to use, and inexpensive dosimeter must be developed that not only measures the physical dose, but which can also distinguish between proton and neutron contributions. To that end, plastic optical fibers with scintillation materials (Gd2O2S:Tb, Gd2O2S:Eu, and YVO4:Eu) were irradiated with protons and neutrons. It was confirmed that sensors with different scintillation materials have different sensitivities to protons and neutrons. A combination of these three scintillators can be used to build a detector array to create a biological dosimeter. [ABSTRACT FROM AUTHOR]

The article presents results of research and development in creating new combined neutron-detecting materials based on scintillating polymer elements, as well as actinide dioxide radiators. New functional combinations of materials for detecting neutrons in a wide energy range are proposed. The obtained spectral and counting rate characteristics of the samples can be used in the selective detection of neutron flux components and the subsequent separation of signals. [ABSTRACT FROM AUTHOR]

Fast and heavy inorganic scintillators with suitable radiation tolerance are required to face the challenges presented at future hadron colliders of high energy and intensity. Up to 5 GGy and 5 × 1018 neq/cm2 of one-MeV-equivalent neutron fluence is expected by the forward calorimeter at the Future Hadron Circular Collider. This paper reports the results of an investigation of proton- and neutron-induced radiation damage in various fast and heavy inorganic scintillators, such as LYSO:Ce crystals, LuAG:Ce ceramics, and BaF2 crystals. The experiments were carried out at the Blue Room with 800 MeV proton fluence up to 3.0 × 1015 p/cm2 and at the East Port with one MeV equivalent neutron fluence up to 9.2 × 1015 neq/cm2, respectively, at the Los Alamos Neutron Science Center. Experiments were also carried out at the CERN PS-IRRAD proton facility with 24 GeV proton fluence up to 8.2 × 1015 p/cm2. Research and development will continue to develop LuAG:Ce ceramics and BaF2:Y crystals with improved optical quality, F/T ratio, and radiation hardness. [ABSTRACT FROM AUTHOR]

Construction of neutron energy spectrum is of interest in various scientific fields such as nuclear power, nuclear security, industrial applications of nuclear and fundamental physics. A genetic neutron spectrum unfolding method is proposed to generate neutron energy spectrum giving light output data from a liquid organic scintillation detector. The method presented attempts to unfold given minimum a priori data, specifically it does not require an initial guess spectrum to be supplied. Two response matrices corresponding to an EJ-309 organic liquid scintillator are constructed for testing, with one matrix using the traditional discretisation and the other using an alternate discretisation based on the energy-to-light conversion process. Test cases include MCNPX-PoliMi simulated 252 Cf, AmLi and AmBe spectra with corresponding detector responses. The genetic method can perform a coarse unfolding of the test spectra, potentially enough to perform an initial categorisation of the spectra. Promising results are obtained when genetic method is used in conjunction with the existing MAXED unfolding code, which operates on the maximum entropy principle. In this scenario, accuracy appears to exceed MAXED using its built-in default a priori spectrum. The 252 Cf test case saw a reduction in the unfolded spectrum error from 5.08 × 10 - 3 to 9.42 × 10 - 5 . The AmLi and AmBe test cases could not be unfolded by MAXED using its default spectrum; however, when supplied with the genetic method result, MAXED could complete a successful unfold. [ABSTRACT FROM AUTHOR]

Imaging using scintillators is a widespread and cost-effective approach in radiography. While different types of scintillator and sensor configurations exist, it can be stated that the detection efficiency and resolution of a scintillator-based system strongly depend on the scintillator material and its thickness. Recently developed event-driven detectors are capable of registering spots of light emitted by the scintillator after a particle interaction, allowing to reconstruct the Center-of-Mass of the interaction within the scintillator. This results in a more precise location of the event and therefore provides a pathway to overcome the scintillator thickness limitation and increase the effective spatial resolution of the system. Utilizing this principle, we present a detector capable of Time-of-Flight imaging with an adjustable field-of-view, ad-hoc binning and re-binning of data based on the requirements of the experiment including the possibility of particle discrimination via the analysis of the event shape in space and time. It is considered that this novel concept might replace regular cameras in neutron imaging detectors as it provides superior detection capabilities with the most recent results providing an increase by a factor 3 in image resolution and an increase by up to a factor of 7.5 in signal-to-noise for thermal neutron imaging. [ABSTRACT FROM AUTHOR]

Fast and heavy inorganic scintillators with suitable radiation tolerance are required to face the challenges presented at future hadron colliders of high energy and intensity. Up to 5 GGy and 5 × 1018 neq/cm2 of one-MeV-equivalent neutron fluence is expected by the forward calorimeter at the Future Hadron Circular Collider. This paper reports the results of an investigation of proton- and neutron-induced radiation damage in various fast and heavy inorganic scintillators, such as LYSO:Ce crystals, LuAG:Ce ceramics, and BaF2 crystals. The experiments were carried out at the Blue Room with 800 MeV proton fluence up to 3.0 × 1015 p/cm2 and at the East Port with one MeV equivalent neutron fluence up to 9.2 × 1015 neq/cm2, respectively, at the Los Alamos Neutron Science Center. Experiments were also carried out at the CERN PS-IRRAD proton facility with 24 GeV proton fluence up to 8.2 × 1015 p/cm2. Research and development will continue to develop LuAG:Ce ceramics and BaF2:Y crystals with improved optical quality, F/T ratio, and radiation hardness.

This article presents a composite (COM) method to obtain the high-resolution pulse shape discrimination (PSD) for the neutron and gamma-ray pulses generated from scintillation detectors. The method, which is based on a selective combination of the digital charge integration (DCI) with the reference pulse method, aims to reduce the mixed radiation events in the low-energy range. An EJ-301 liquid scintillation detector together with a fast sampling analog-to-digital converter (ADC) is used to measure and digitize the pulses induced from the radioactive decays of 60Co and 252Cf, which are then analyzed by our COM method. The proposed method is evaluated using the figure of merit (FoM) and separation quality function $F(u)$ , and the results are compared with three known methods, namely the DCI, standard event fit (SEF), and artificial neural network (ANN) methods. We show that the average values of FoM and $F(u)$ obtained within the COM method are about ten times higher than those obtained within the DCI and SEF in the whole energy range from 50 to 1000 keV electron equivalent (keVee). In particular, by using the COM method, the percentage of gamma events being confused as neutrons ranges from 0.32% to 8.80% when the energy is reduced from 400 to 50 keVee. This finding, which is significantly lower than those obtained by using the DCI and SEF, indicates that the proposed COM method should be considered as a leading method for producing a neutron/gamma PSD counter system with high resolution. [ABSTRACT FROM AUTHOR]

As a result of the modernization of the DRG-05M dosimeter, a convenient device was obtained, which allows estimating the level of gamma- and X-ray radiation, beta-particles, and neutrons without changing the detector heads. Two devices were manufactured and a third one was prepared for metrological certification. [ABSTRACT FROM AUTHOR]

The development of a neutron detector for real-time measurements in an intense neutron field is desired. We are developing a quartz optical-fiber-based neutron detector as a real-time neutron monitor. Thus far, Eu:LiCaAlF6 crystals and LiF/Eu:CaF2 eutectics have been used as the scintillators of the quartz optical-fiber-based neutron detectors. These scintillators have high light yields, but relatively long decay time constants, which are the limiting factors for the dynamic range of optical-fiber-based neutron detectors. In this work, we applied a small Li glass scintillator to a quartz optical-fiber-based neutron detector using an optical fiber with high numerical aperture and a UV-curable resin with high transmittance. The fabricated detector showed a clear peak corresponding to neutron events in the pulse height distribution. The radiation resistance was evaluated and no deterioration was observed up to 2 x 1012 n/cm². The detector output linearity was confirmed up to 450 kcps, which was about ten times larger than that of the detector using the conventional Eu:LiCaAlF6 or LiF/Eu:CaF2 scintillator. [ABSTRACT FROM AUTHOR]

In the course of a controllable thermonuclear fusion reaction the state of the plasma in the reactor must be monitored. Neutron diagnostics can provide some parameters of the plasma in the thermonuclear reactor. In the present work, the neutron diagnostics of the equatorial port of the ITER is checked by means of Monte Carlo modeling of seven external fast-neutron spectrometers based on solid stilbene scintillators distributed in the port with their collimators and the efficiency of the spectrometers is determined. [ABSTRACT FROM AUTHOR]

• A technique for the clustering of electrical signals is proposed. • The clustering algorithm has been customized for the electrical pulses from high-energy particle detectors. • Clustering has been applied on the electrical signal coming from scintillator under radiation. • The ability to identify neutrons and gamma patterns has been verified. In several nuclear applications, scintillators, coupled with a photomultiplier and pulse amplifier, are used in order to detect high energy particles, i.e. neutrons and gamma rays. The different particles incident on the scintillator produce electrical pulses having different shape; moreover, the amplitude of these signals is related to the particles energy. The electrical pulses of the scintillator chain are acquired by digital systems that, generally, perform a triggered acquisition consisting of a stream of pulse windows. The aim of this study is the development of a simplified clustering algorithm able to produce reference patterns in compliance with the pattern recognition algorithm based on the matched filter technique, starting from a stream of pulses generated by particles having different energy and type. This paper contains a general description of the clustering algorithm and of the main customizations performed for the scintillator signals. In order to test in real case the efficiency, the algorithm has been applied on the data acquired during a radiation test performed at Frascati Neutron Generator for Stilbene scintillator. The results show that this algorithm works properly, deriving the centroids of the clusters representing the neutron and gamma shapes, together with their occurrences in the analysed data stream. [ABSTRACT FROM AUTHOR]

The lifetime of the state of 135Te has been measured to be τ = 809(22) ps, corresponding to a reduced transition rate of =6.6(2) W.u. The experiment was performed at the focal point of the Lohengrin spectrometer and μs-delayed γ rays from mass-selected A = 135 ions were detected by four LaBr3(Ce) scintillators. This allowed the fast-timing technique to be used to access lifetimes in the 10s-of-ps to ns time region. The value is typical of a vibrational transition, despite 135Te possessing only one valence neutron and two valence protons. Shell model calculations performed with the state-of-the-art effective interaction predict a B(E2) value close to the experimental one and show that contributions from the π(g7/2, d5/2)νf7/2 couplings are coherent. [ABSTRACT FROM AUTHOR]

In this study, charge compensation was performed by co-doping Na + ions at the Ca2+ sites of Ce-doped LiCaAlF 6 single crystals to prevent the generation of cation vacancies owing to Ce3+-doping at the Ca2+ sites. Consequently, an improved radiation resistance and increased light yield under neutron irradiation was achieved. In contrast, the Al metal of the starting material used as a substitute for AlF 3 significantly increased the effective segregation coefficient k eff of the Eu2+ ions in Eu-doped LiCaAlF 6 and Eu-doped LiSrAlF 6 single crystals. The Al metal and EuF 3 in the starting materials produced EuF 2 via a chemical reaction, and the Eu2+ ions in EuF 2 could be substituted at the Ca2+ and Sr2+ sites. In addition, the Ca/Sr ratio control of the Li(Ca,Sr)AlF 6 :Eu solid-solution scintillator single crystals improved the light yield through band-gap control, and the Li(Ca,Sr)AlF 6 :Eu single crystal with a 25% Sr concentration exhibited the highest light yield. Charge compensation was conducted using Na co-doping to improve the radiation resistance of the LiCAF:Ce single crystals, thereby preventing the generation of cation defects by the Ce3+-doping at the Ca2+ site. It was determined that the improvement in the radiation resistance of the LiCAF:Ce single crystal via Na co-doping can contribute to the improvement in the durability of the production of LiCAF:Ce single crystals. [Display omitted] • Scintillation properties of LiCaAlF 6 and LiSrAlF 6 single crystals were improved by chemical composition control. • Charge compensation by Na co-doping for LiCAF:Ce single crystals prevents generations of cation vacancies by Ce3+-doping. • Al metal greatly increases the segregation coefficient of Eu ion in the LiCAF and LiSAF single crystals. • Effective segregation coefficient of Eu2%,AlM1%:LiSrAlF 6 crystal was improved to 0.986 using the Al metal. • Ca/Sr ratio control in the Eu:Li(Ca,Sr)AlF 6 single crystals improves the light yield under thermal neutron irradiation. [ABSTRACT FROM AUTHOR]

This paper describes the high-priority testing activities supporting the ITER radial neutron camera (RNC) design, performed by a consortium of European institutes within a framework contract placed by fusion for energy, the ITER European Domestic Agency. The main role of the RNC is to measure the uncollided 14- and 2.5-MeV neutrons from deuterium–tritium and deuterium–deuterium fusion reactions through an array of flux monitors/spectrometers located in collimated lines of sight viewing the plasma through the ITER equatorial port plug #1. The line-integrated neutron fluxes will be used to evaluate, through reconstruction techniques, the radial profile of the neutrons emitted per unit time and volume (neutron emissivity) and, therefore, the neutron yield and the alpha particles’ birth profile. The activity of high-priority testing is dedicated to the preparation and the design of experimental test environment, the conduction of appropriate tests and reporting of test results for the high-priority prototypes, clarifying or verifying the expected key function and system behavior, and enhancing learning on specific issues (potential showstoppers). [ABSTRACT FROM AUTHOR]

The electrical pattern recognition can be useful in several applications; generally it is used to detect particular events or anomalies in the signal under analysis or to identify precursors, especially in electrophysiology. Each application requires customized algorithms and appropriate signal processing capabilities. In this article we present the pattern recognition applied to neutron and gamma scintillator analysis; the algorithm can be used considering that the incident particles on the detector produce pulses having different shape. The discrimination of particles is performed starting from a reference patterns set. The algorithm has been designed to be efficiently implemented in programmable logic gate array; anyway, considering the broadband of the signals under analysis, the real time implementation needs simply reference set based on a limited number of patterns due to technological constrains. The algorithm can also be applied off line by using a more complex reference pattern sets in order to detect and to classify the pile-up event, or to compress the scintillator data. The proposed pattern recognition algorithm is based on the cross-correlation operator and on the Euclidean distance between the reference pattern and the shape of the signal under analysis. The automatic pattern recognition algorithm and its simulations are reported in the article. In order to verify the performances in the case of scintillator signals, the algorithm has been applied on data acquired by two scintillator systems irradiated by a neutron-γ source at the Frascati Tokamak Upgrade laboratories. The results confirm the suitability of the method and its future usability. With minor changes the systems can be used in different diagnostic fields. [ABSTRACT FROM AUTHOR]

We show that Li 2 Se:Te is a potential neutron scintillator material based on density functional calculations. Li 2 Se exhibits a number of properties favorable for efficient neutron detection, such as a high Li concentration for neutron absorption, a small effective atomic mass and a low density for reduced sensitivity to background gamma rays, and a small band gap for a high light yield. Our calculations show that Te doping should lead to the formation of deep acceptor complex V Li –Te Se , which can facilitate efficient light emission, similar to the emission activation in Te doped ZnSe. [ABSTRACT FROM AUTHOR]

The pulsed ion beam from a vacuum arc source in a compact sealed-tube neutron generator owns many special features, such as multiparticle mixture beams, high-intensity beams, short pulsewidth beams, transporting in a single gap acceleration system, and eccentric beams. Beam profile and composition are useful information for designing a high-intensity sealed-tube neutron generator, especially for the insulation withstand of the device, the life of the tritium target, the neutron yield, and so on. An improved traditional online diagnostic method that uses an aluminum-coated scintillator screen and a novel offline diagnostic method that is based on secondary ion mass spectrometry are introduced, respectively. The preliminary experimental results can show the intensity distribution of the ion beam profile and the composition with high resolution. The results from the two methods can fit each other well. [ABSTRACT FROM PUBLISHER]

Deuterated polyethylene targets have been irradiated by means of a 1016 W/cm2 laser using 600 J pulse energy, 1315 nm wavelength, 300 ps pulse duration and 70 micron spot diameter. The plasma parameters were measured using on-line diagnostics based on ion collectors, SiC detectors and plastic scintillators, all employed in time-of-flight configuration. In addition, a Thomson parabola spectrometer, an X-ray streak camera, and calibrated neutron dosimeter bubble detectors were employed. Characteristic protons and neutrons at maximum energies of 3.0 MeV and 2.45 MeV, respectively, were detected, confirming that energy spectra of reaction products coming from deuterium-deuterium nuclear fusion occur. In thick advanced targets a fusion rate of the order of 2 × 108 fusions per laser shot was calculated. [ABSTRACT FROM AUTHOR]

Abstract: Knowledge of prompt fission γ-ray emission has been of major interest in reactor physics for a few years. Since very few experimental spectra were ever published until now, new measurements would be also valuable to improve our understanding of the fission process. An experimental method is currently being developed to measure the prompt fission γ-ray spectrum from some tens keV up to 10 MeV at least. The mean multiplicity and total energy could be deduced. In this method, the γ-rays are measured with a bismuth germanate (BGO) detector which has the advantage to present a high P/T ratio and a high efficiency compared to other γ-ray detectors. The prompt fission neutrons are rejected by the time of flight technique between the BGO detector and a fission trigger given by a fission chamber or a scintillating active target. Energy and efficiency calibration of the BGO detector were carried out up to 10.76 MeV by means of the 27Al(p,γ) reaction. First prompt fission γ-ray spectrum measurements performed for the spontaneous fission of 252Cf and for 1.7 and 15.6 MeV neutron-induced fission of 238U at the CEA, DAM, DIF Van de Graaff accelerator, will be presented. [Copyright &y& Elsevier]

This paper reports on a small-scale radiation detector that is sensitive to alpha, beta, gamma, and neutron radiation using scintillators doped with boron nanoparticles utilizing CMOS fabrication techniques. Two types of microscintillators have been fabricated and tested: One relies on sintered glass frit doped with boron nanoparticles, and the other uses quartz with boron diffused into the substrate. Radiation impinging on the scintillation matrix produces varying optical pulses of varying intensities depending on the type of radiation particle. The optical pulses are differentiated by on-chip pulse height spectroscopy and recorded on a microcontroller. The pulse height circuitry has been fabricated with both discrete circuits and designed into a single integrated circuit package. The quartz substrates have shown to be more transparent to the wavelength of the created optical pulses, which results in a higher count rate when compared to the tested glass scintillator. The quartz scintillator also shows better absorption of radiation particles, resulting in better detection efficiencies than the glass. The quartz also has been tested with varying doping levels and has the ability to detect neutrons. Source differentiation between ^137\Cs and ^60\Co has also been demonstrated. \hfill[2010-0285] [ABSTRACT FROM AUTHOR]

Neutrons from deuteron-deuteron fusion reactions were used for the study of pinch dynamics in a modified small plasma-focus device at a current peak of 200 kA. In front of the inner electrode (anode), an antielectrode was placed. Neutron yield reached 105 - 107 per shot. The time-resolved neutron signals were registered with two scintillation detectors positioned end-on and side-on at the same distance of 150 cm from the interelectrode gap. They enabled the comparison of difference in energies and estimation of directions of fast deuterons producing neutrons. The XUV frames imaged the pinch configuration at the moment of X-ray and neutron emission and differed in shots with high and low neutron yields. Interferograms enabled the evaluation of distribution of plasma density. The presence of the antianode decreased the neutron yield and influenced the distribution of the plasma density in front of the anode. [ABSTRACT FROM AUTHOR]

Abstract: At JET, the NE213 liquid scintillator is being validated as a diagnostic tool for spectral measurements of neutrons emitted from the plasma. Neutron spectra have to be unfolded from the measured pulse-height spectra, which is an ill-conditioned problem. Therefore, use of two independent unfolding methods allows for less ambiguity on the interpretation of the data. In parallel to the routine algorithm MAXED based on the Maximum Entropy method, the Minimum Fisher Regularisation (MFR) method has been introduced at JET. The MFR method, known from two-dimensional tomography applications, has proved to provide a new transparent tool to validate the JET neutron spectra measured with the NE213 liquid scintillators. In this article, the MFR method applicable to spectra unfolding is briefly explained. After a mention of MFR tests on phantom spectra experimental neutron spectra are presented that were obtained by applying MFR to NE213 data in selected JET experiments. The results tend to confirm MAXED observations. [Copyright &y& Elsevier]

We report the results of test measurements aimed at determining the performances of 6Li doped glass scintillators for the detection of ultra-cold neutrons. Four types of scintillators, GS1, GS3, GS10 and GS20, which differ by their 6Li concentrations, have been tested. The signal to background separation is fully acceptable. The relative detection efficiencies have been determined as a function of the neutron velocity. We find that GS10 has a higher efficiency than the others for the detection of neutrons with velocities below 7 m/s. Two pieces of scintillators have been irradiated with a high flux of cold neutrons to test the radiation hardness of the glasses. No reduction in the pulse height has been observed up to an absorbed neutron dose of 1 x 1013 cm-3. [ABSTRACT FROM AUTHOR]