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Neutron powder diffraction measurements of 0.9 mm3of mixture of deuterated brucite and pressure medium were conducted at pressures to 2.8 GPa, using an opposed anvil cell and a medium-resolution diffractometer at Japan Proton Accelerator Research Complex pulsed neutron source. Spurious-free diffraction patterns were successfully obtained and refined to provide all structural parameters including Debye–Waller factors. Tilting of hydroxyl dipoles of brucite toward one of the three nearest-neighbor oxygen anions was confirmed to be substantial at pressure as low as 1.5 GPa. By this application, technical feasibility to analyze such a small sample has been newly established, which would be useful to extend the applications of neutron diffraction at high pressures. [ABSTRACT FROM PUBLISHER]

The sharp variation of neutron attenuation at certain energies specific to particular nuclides (the lower range being from ~1eV up to ~1keV), can be exploited for the remote mapping of element and/or isotope distributions, as well as temperature probing, within relatively thick samples. Intense pulsed neutron beam-lines at spallation sources combined with a high spatial, high-timing resolution neutron counting detector, provide a unique opportunity to measure neutron transmission spectra through the time-of-flight technique. We present the results of experiments where spatially resolved neutron resonances were measured, at energies up to 50keV. These experiments were performed with the intense flux low background NOBORU neutron beamline at the J-PARC neutron source and the high timing resolution (~20ns at epithermal neutron energies) and spatial resolution (~55µm) neutron counting detector using microchannel plates coupled to a Timepix electronic readout. Simultaneous element-specific imaging was carried out for several materials, at a spatial resolution of ~150µm. The high timing resolution of our detector combined with the low background beamline, also enabled characterization of the neutron pulse itself – specifically its pulse width, which varies with neutron energy. The results of our measurements are in good agreement with the predicted results for the double pulse structure of the J-PARC facility, which provides two 100ns-wide proton pulses separated by 600ns, broadened by the neutron energy moderation process. Thermal neutron radiography can be conducted simultaneously with resonance transmission spectroscopy, and can reveal the internal structure of the samples. The transmission spectra measured in our experiments demonstrate the feasibility of mapping elemental distributions using this non-destructive technique, for those elements (and in certain cases, specific isotopes), which have resonance energies below a few keV, and with lower resolution for elements with relatively high resonance energies in the 1–30keV range. [ABSTRACT FROM AUTHOR]

The article offers information on the physical design of the target station for the China Spallation Neutron Source. Topics cited include the production of pulsed neutrons using tungsten target under the collision of a pulsed proton beam, neutron instruments used to determine the microscopic structure and dynamics of atoms and their spin in a condensed substance, and users activities.

Abstract: In the framework of the EURADOS working group 11, an intercomparison of active neutron survey meters was performed in a pulsed neutron field (PNF). The aim of the exercise was to evaluate the performances of various neutron instruments, including commercially available rem-counters, personal dosemeters and instrument prototypes. The measurements took place at the cyclotron of the Helmholtz-Zentrum Berlin für Materialien und Energie GmbH. The cyclotron is routinely used for proton therapy of ocular tumours, but an experimental area is also available. For the therapy the machine accelerates protons to 68MeV. The interaction of the proton beam with a thick tungsten target produces a neutron field with energy up to about 60MeV. One interesting feature of the cyclotron is that the beam can be delivered in bursts, with the possibility to modify in a simple and flexible way the burst length and the ion current. Through this possibility one can obtain radiation bursts of variable duration and intensity. All instruments were placed in a reference position and irradiated with neutrons delivered in bursts of different intensity. The analysis of the instrument response as a function of the burst charge (the total electric charge of the protons in the burst shot onto the tungsten target) permitted to assess for each device the dose underestimation due to the time structure of the radiation field. The personal neutron dosemeters were exposed on a standard PMMA slab phantom and the response linearity was evaluated. [Copyright &y& Elsevier]

Abstract: An intercomparison of the performances of active neutron detectors was carried out in pulsed neutron fields in the new HiRadMat facility at CERN. Five detectors were employed: four of them (two ionization chambers and two rem counters) are routinely employed in the CERN radiation monitoring system, while the fifth is a novel instrument, called LUPIN, specifically conceived for applications in pulsed neutron fields. The measurements were performed in the stray field generated by a proton beam of very short duration with momentum of 440 GeV/c impinging on a dump. The beam intensity was steadily increased during the experiment by more than three orders of magnitude, with an H*(10) due to neutrons at the detector reference positions varying between a few nSv per burst and a few μSv per burst, whereas the gamma contribution to the total H*(10) was negligible. The aim of the experiment was to evaluate the linearity of the detector response in extreme pulsed conditions as a function of the neutron burst intensity. The results show that the ionization chambers have a quasi-linear response, very close to the ideal behaviour also for values of H*(10) of a few μSv/burst; the LUPIN response shows a slight deviation from the ideal curve when the H*(10) per burst is higher than 100 nSv; the rem counters response are characterized by a strong deviation from the linearity for H*(10) values higher than a few tens of nSv. [Copyright &y& Elsevier]

In this work we present a systematic study of Japanese sword hand-guards ( tsuba) carried out by means of non-invasive techniques using neutrons. Several tsuba from different periods, belonging to the Japanese Section of the Stibbert Museum, were analysed using an innovative approach to characterise the bulk of the samples, coupling two neutron techniques, namely Time of Flight Neutron Diffraction (ToF-ND) and Nuclear Resonance Capture Analysis (NRCA). The measurements were carried out on the same instrument: the INES beam-line at the ISIS spallation pulsed neutron source (UK). NRCA analysis allows identifying the elements present in the sample gauge volume, while neutron diffraction is exploited to quantify the phase distribution and other micro-structural parameters of the metal specimen. The results show that all samples are made of high-quality metal, either steel or copper alloy, with noticeable changes in composition and working techniques, depending on the place and time of manufacturing. [ABSTRACT FROM AUTHOR]

Highlights: [•] Definition of a spatial correction factor for the experimental prompt neutron decay constant. [•] Introduction of a MCNP6 calculation methodology to simulate Rossi-alpha distribution for pulsed neutron sources. [•] Comparison of MCNP6 results with experimental data for count rate, Rossi-alpha, and Feynman-alpha distributions. [•] Improvement of the comparison between numerical and experimental results by taking into account the dead-time effect. [Copyright &y& Elsevier]

An archaeological survey method based on neutron gamma-ray logging is described. The method relies on the measurement of capture gamma radiation induced by neutron irradiation from a pulsed generator. This technique provides elemental information on the irradiated zone by spectroscopic analysis of the gamma-ray data. This approach has been studied with Geant4 Monte Carlo simulations. In particular, irradiation volume for a deuterium–deuterium and deuterium–tritium (D-T) neutron generator and sampling volume for the D-T source were estimated. In addition, a neutron log response, which illustrates the capability of the neutron tool to localize artifacts lying beneath the surface, is shown. [ABSTRACT FROM AUTHOR]

A new technique of inelastic neutron scattering measurement utilizing the multiple incident energies is applied to the dynamical study of vitreous silica. A wide variety of extracted information from a series of two-dimensional maps of dynamical structure factor with multiple different incident energies are greatly valuable. The applicability and its expected contribution of new experimental technique into the further progress of scientific activities in solid state ionic materials are discussed.

Abstract: The Italian Neutron Experimental Station (INES) located at the ISIS pulsed neutron source (Didcot, United Kingdom) provides a thermal neutron beam mainly used for diffraction analysis. A neutron transmission imaging system was also developed for beam monitoring and for aligning the sample under investigation. Although the time-of-flight neutron diffraction is a consolidated technique, the neutron imaging setup is not yet completely characterized and optimized. In this paper the performance for neutron radiography and tomography at INES of two scintillator screens read out by two different commercial CCD cameras is compared in terms of linearity, signal-to-noise ratio, effective dynamic range and spatial resolution. In addition, the results of neutron radiographies and a tomography of metal alloy test structures are presented to better characterize the INES imaging capabilities of metal artifacts in the cultural heritage field. [Copyright &y& Elsevier]

Highlights: [•] Several tools were used to monitor the change in saturation and migration of CO2 in the reservoir. [•] Measurements included pulsed neutron, sonic, resistivity and crosswell seismic. [•] Pulsed neutron log provided good answers but is limited to the near wellbore. [•] Resistivity and sonic had difficulty due to complicated wellbore construction. [•] Crosswell seismic provided good information between wells but due to the source size it could not be run in tubing. [Copyright &y& Elsevier]

Abstract: We performed a time-of-flight (TOF) single-crystal neutron diffraction experiment with a diffractometer (the IBARAKI Biological Crystal Diffractometer (iBIX)) using single-crystal silicon, and we determined several candidates for fundamental fitting functions to faithfully reproduce the Bragg reflection profile with asymmetries in the TOF direction. The Vavilov and Landau distributions used to describe the energy loss of charged particles traversing a thin absorber were found to be in excellent agreement with the observed TOF profile. We have evaluated the obtained functions and the convolution of back-to-back exponentials with a Gaussian to determine which function provides the best fit to the data. Further, we have applied the obtained functions to the practical Bragg reflection profiles of proteins after subtraction of the background using the Statistics-sensitive Nonlinear Iterative Peak-clipping (SNIP) algorithm. [Copyright &y& Elsevier]

Abstract: A new method to accurately determine gas saturation in the tight gas reservoir using a three-detector pulsed neutron logging tool was proposed. Formation porosity is varied from 2% to 15% to simulate the distribution of thermal neutron under different borehole and formation conditions by using Monte Carlo method. The study result shows that the difference of three detectors counts can be used to determine gas saturation and have higher sensitivity than counting the ratio of different detectors. [Copyright &y& Elsevier]

Abstract: Neutron interrogation facilities for mass evaluation of Special Nuclear Materials (SNM) samples are divided into two main categories: passive interrogation, where all neutron detections are due to spontaneous events, and active interrogation, where fissions are induced on the tested material by an external neutron source. While active methods are, in general, faster and more effective, their analysis is much harder to carry out. In the paper, we will introduce a new formalism for analyzing the detection signal generated by a pulsed source active interrogation facility. The analysis is aimed to distinct between fission neutrons from the main neutron source in the system, and the surrounding “neutron noise”. In particular, we derive analytic expressions for the first three central moments of the number of detections in a given time interval, in terms of the different neutron sources. While the method depends on exactly the same physical assumptions as known models, the simplicity of the suggested formalism allows us to take into account the variance of the external neutron source—an effect that was so far neglected. [Copyright &y& Elsevier]

Development of a palm top plasma focus device generating (5.2 ± 0.8) × 104 neutrons/pulse into 4π steradians with a pulse width of 15 ± 3 ns is reported for the first time. The weight of the system is less than 1.5 kg. The system comprises a compact capacitor bank, a triggered open air spark gap switch, and a sealed type miniature plasma focus tube. The setup is around 14 cm in diameter and 12.5 cm in length. The energy driver for the unit is a capacitor bank of four cylindrical commercially available electrolytic capacitors. Each capacitor is of 2 μF capacity, 4.5 cm in diameter, and 9.8 cm in length. The cost of each capacitor is less than US$ 10. The internal diameter and the effective length of the plasma focus unit are 2.9 cm and 5 cm, respectively. A DC to DC converter power supply powered by two rechargeable batteries charges the capacitor bank to the desired voltage and also provides a trigger pulse of -15 kV to the spark gap. The maximum energy of operation of the device is 100 J (8 μF, 5 kV, 59 kA) with deuterium gas filling pressure of 3 mbar. The neutrons have also been produced at energy as low as 36 J (3 kV) of operation. The neutron diagnostics are carried out with a bank of 3He detectors and with a plastic scintillator detector. The device is portable, reusable, and can be operated for multiple shots with a single gas filling. [ABSTRACT FROM AUTHOR]

Abstract: A number of studies focused in the last decades on the development of survey meters to be used in pulsed radiation fields. This is a topic attracting widespread interest for applications such as radiation protection and beam diagnostics in accelerators. This paper describes a new instrument specifically conceived for applications in pulsed neutron fields (PNF). The detector, called LUPIN, is a rem counter type instrument consisting of a 3He proportional counter placed inside a spherical moderator. It works in current mode with a front-end electronics consisting of a current–voltage logarithmic amplifier, whose output signal is acquired with an ADC and processed on a PC. This alternative signal processing allows the instrument to be used in PNF without being affected by saturation effects. Moreover, it has a measurement capability ranging over many orders of burst intensity. Despite the fact that it works in current mode, it can measure a single neutron interaction. The LUPIN was first calibrated in CERN''s calibration laboratory with a PuBe source. Measurements were carried out under various experimental conditions at the Helmholtz-Zentrum in Berlin, in the stray field at various locations of the CERN Proton Synchrotron complex and around a radiotherapy linear accelerator at the S. Raffaele hospital in Milan. The detector can withstand single bursts with values of H⁎(10) up to 16nSv/burst without showing any saturation effect. It efficiently works in pulsed stray fields, where a conventional rem-counter underestimates by a factor of 2. It is also able to reject the very intense and pulsed photon contribution that often accompanies the neutron field with good reliability. [Copyright &y& Elsevier]

We report the Fermi Large Area Telescope discovery of γ -ray pulsations from the 22.7 ms pulsar A in the double pulsar system J0737-3039A/B. This is the first mildly recycled millisecond pulsar (MSP) detected in the GeV domain. The 2.7 s companion object PSR J0737-3039B is not detected in γ rays. PSR J0737-3039A is a faint γ -ray emitter, so that its spectral properties are only weakly constrained; however, its measured efficiency is typical of other MSPs. The two peaks of the γ -ray light curve are separated by roughly half a rotation and are well offset from the radio and X-ray emission, suggesting that the GeV radiation originates in a distinct part of the magnetosphere from the other types of emission. From the modeling of the radio and the γ -ray emission profiles and the analysis of radio polarization data, we constrain the magnetic inclination α and the viewing angle ζ to be close to 90°, which is consistent with independent studies of the radio emission from PSR J0737-3039A. A small misalignment angle between the pulsar's spin axis and the system's orbital axis is therefore favored, supporting the hypothesis that pulsar B was formed in a nearly symmetric supernova explosion as has been discussed in the literature already. [ABSTRACT FROM AUTHOR]

An adaptation of the differential die away (DDA) technique, which enhances the detection of fissile materials, has been developed and demonstrated in the laboratory. The differential time-of-flight (DTOF) technique applies to situations where special nuclear material (SNM) is located some distance (up to a few meters) away, is accessible from only one side, and is either bare or embedded in an environment that is slightly neutron moderating, and where the more conventional DDA pulsed neutron source technique is less effective. The technique is based on the fission reaction of thermal neutrons with fissile material, if present. The thermal neutrons are furnished by the moderation of neutrons from an electronic neutron generator (ENG). Fast neutrons are generated in relatively narrow pulses of tens to hundreds of microseconds. They are slowed down in a suitable moderator surrounding the source. The time of flight (TOF) of these neutrons, before arrival at the SNM, spreads over orders of magnitude due to the wide spread in their velocities, which lead to a time spread of the neutron-induced fission in the SNM. Neutron signatures resulting from the fissions, e.g., prompt fast neutrons (as well as few delayed neutrons) can then be detected by fast neutron detectors well after the original source neutrons have died away. [ABSTRACT FROM PUBLISHER]

Abstract: We measured two-dimensional transmission spectra of pulsed neutron beams for a Japanese sword sample. Atom density, crystalline size, and preferred orientation of crystals were obtained using the RITS code. The position dependence of the atomic density is consistent with the shape of the sample. The crystalline size is very small and shows position dependence, which is understood by the unique structure of Japanese swords. The preferred orientation has strong position dependence. Our study shows the usefulness of the pulsed neutron transmission method for cultural metal artifacts. [Copyright &y& Elsevier]

Abstract: The RITS code was developed for quantitative evaluation and visualization of crystalline structural information (e.g. crystallographic texture, preferred crystal orientation, crystallite block size and crystal lattice strain, etc.) of a material, analyzing position-dependent Bragg edge transmission spectra measured in an imaging experiment with pulsed neutrons. Originally, this code was neither able to deal with all the crystal structures that were classified into 230 types of space groups, nor applicable to materials composed of multi elements and multi crystalline phases. Therefore, we improved the RITS code for expansion of its capability, and then performed some demonstrations of simulation calculations and profile fitting analyses of experimental data. In this article, we present the new algorithm and the new functions of the improved RITS code, and the results of the simulation calculations and the experimental data analyses. [Copyright &y& Elsevier]

Abstract: Neutron resonance absorption radiography is a technique to enhance neutron transmission images of specific nucleus at neutron resonance energies. Demonstration measurements by using a lithium-glass pixel type scintillator and a gas electron multiplication (GEM) neutron detector were carried out at NOBORU beam line in MLF/J-PARC for sodium, manganese, cobalt, copper, zinc, molybdenum, cadmium, indium, tantalum and gold. To discuss advantages of the resonance absorption radiography the mass attenuation coefficient at resonance energy of each element was compared to that at 25 meV. In addition a visibility index derived by a resonance peak cross section and a relative width (full width at half maximum divided by its resonance energy) was proposed to summarize visibility of the neutron resonance absorption radiography for natural elements. The values of visibility index and the resonance energy indicated that large advantages of the resonance absorption radiography were obtainable for the following elements: sodium (Na), manganese (Mn), cobalt (Co), rhodium (Rh), silver (Ag), cadmium (Cd), indium (In), xenon (Xe), cesium (Cs), samarium (Sm), europium (Eu), dysprosium (Dy), erbium (Er), thulium (Tm), hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), iridium (Ir) and gold (Au). [Copyright &y& Elsevier]

Abstract: A new facility for combined neutron imaging and neutron diffraction called IMAT is currently being built at the pulsed neutron spallation source ISIS in the United Kingdom. Analytical techniques will include neutron radiography, neutron tomography, energy-selective neutron imaging, residual strain analysis and spatially resolved texture analysis. The instrument will be available for a wide range of materials science applications with a main emphasis on engineering studies. It is expected that IMAT will start operation in 2015. [Copyright &y& Elsevier]

Abstract: Pulsed neutron imaging methods provide information on crystallographic structure, magnetic field, elemental composition, hydrogen bound state and other material features. Such methods have been expected to be a powerful complement to the traditional imaging method. Data analysis codes, detectors and new applications are being developed in Japan, and a new imaging beam line is being constructed at J-PARC. Here, recent progress in Japanese research on pulsed neutron imaging is presented, and a design for construction of the new imaging beam line is reported. [Copyright &y& Elsevier]

Abstract: A small neutron facility based on a compact accelerator has some advantages over a large facility in terms of accessibility and usability. One of main objects of a compact accelerator neutron source is neutron imaging. Therefore, we performed an optimization study on a pulsed thermal neutron source and an epithermal one based on a compact accelerator in order to use it for thermal neutron imaging and resonance neutron imaging. We have carried out simulation calculations to evaluate the neutron intensity change depending on the moderator size taking into account spatial resolution. The intensities from a small moderator were higher than that from a larger one when compared at the same L/D. However, field of view (FOV) constrained the minimal moderator size. At L/D of 100 and FOV from 10 to 30cm, the optimal moderator size giving the highest intensity was from 10 to 12cm. [Copyright &y& Elsevier]

Abstract: The prompt decay constant method and the area-ratio (Sjöstrand) method constitute the reference techniques for measuring the reactivity of a subcritical system using Pulsed Neutron Source experiments (PNS). However, different experiments have shown that in many cases it is necessary to apply corrections to the experimental results in order to take into account spectral and spatial effects. In these cases, the approach usually followed is to develop different specific correction procedures for each method. In this work we discuss the validity of prompt decay constant method and the area-ratio method in the Yalina-Booster subcritical assembly and propose a general correction procedure based on Monte Carlo simulations. [Copyright &y& Elsevier]

Abstract: Pulsed neutrons emitted from a plasma focus (PF) device have been used for the first time for the non-destructive assay of 235U content in different chemical forms (oxide and metal). The PF device generates (1.2±0.3)×109 D–D fusion neutrons per shot with a pulse width of 46±5ns. The method involves the measurement of delayed neutrons from an irradiated sample 50ms after exposure to the neutron pulse for a time of about 100s in the multichannel scaling (MCS) mode. The calibration of the active interrogation delayed neutron counter (AIDNEC) system was carried out by irradiating U3O8 samples of varying amounts (0.1–40g) containing enriched 235U (14.8%) in the device. The delayed neutrons were monitored using a bank of six 3He detectors. The sensitivity of the system was found to be about 100counts/s/g over the accumulation time of 25s per neutron pulse of ∼109. The detection limit of the system is estimated to be 18mg of 235U. The system can be suitably modified for applications toward non-destructive assay of fissile content in waste packets. [Copyright &y& Elsevier]

The existence of resonance peaks in neutron absorption spectra in the epithermal range of energies enables unique non-destructive testing techniques. The deep penetration of epithermal neutrons provides an opportunity to perform a compositional analysis of a sample which is opaque to X-rays and thermal neutrons. The neutron resonances in the transmission spectra constitute a characteristic pattern for many isotopes, which can be used to identify the isotope and to map the distribution of the isotope in a sample. The neutron transmission spectra can be measured with the time of flight (TOF) technique using a pulsed neutron source. Combining this method with a high resolution neutron counting detector enables substantial improvements of spatial resolution of neutron resonance transmission imaging. Such a detector has been developed to register neutrons with 55 \mum spatial and 10–1000 ns temporal resolution Our proof-of-principle experiments at the ISIS pulsed neutron spallation source demonstrate that compositional analysis of multi-element samples can now be performed with \sim 150\ \mum spatial resolution. Images of a test mask consisting of <200\ \mum thick foils of Au, Ag, In and Gd were collected in the 1–100 eV energy range. The experimental results demonstrate the potential for compositional analysis via resonance absorption transmission with high spatial resolution. In-bulk temperature measurement through Doppler broadening analysis will also benefit from this technique. [ABSTRACT FROM AUTHOR]

Abstract: The success of shale gas in North America has attracted increased interest in “unconventional” reservoirs. Two critical factors for shale-gas reservoirs are units amenable to hydrologic fracture stimulation and sufficient natural gas content. The effectiveness of hydrologic fracture stimulation is influenced by rock geomechanical properties, which are related to rock mineralogy. The natural gas content in shale reservoirs has a strong relationship with organic matter, which is measured by total organic carbon (TOC). A 3D shale lithofacies model constructed using mineral composition, rock geomechanical properties and TOC content can be applied to optimize the design of horizontal well trajectories and stimulation strategies. Core analysis data, log data and seismic data were used to build a 3D shale lithofacies from core to well and finally to regional scale. Core, advanced and common logs were utilized as inputs to petrophysical analysis, and various pattern recognition methods, such as discriminant analysis, fuzzy logic, neural network and support vector machine. A limited set of eight derived parameters from common logs were determined as critical inputs for pattern recognition methods. Advanced logs, such as pulsed neutron spectroscopy, are used to determine mineral composition and TOC data improve and confirm the quantitative relationship between conventional logs and lithofacies. Seismic data, interpreted sequence stratigraphy and depositional environments were used as constraints to build deterministic and stochastic 3D lithofacies models and to extrapolate lithofacies from well scale to regional scale. [Copyright &y& Elsevier]

Conventional neutron radiography can be strongly enhanced by obtaining Bragg-edge information spatially correlated with the attenuation coefficient. This can now be achieved through time-of-flight techniques at pulsed neutron sources, utilising a neutron counting detector with high-spatial and high-temporal resolution. In these measurements, the positions of Bragg edges can in principle be obtained for each 55 × 55 μm2 pixel of the radiographic image. The combination of both Bragg-edge and attenuation information enables high spatial resolution studies to be carried out on material composition, phase transitions, texture variations, as well as residual strain mapping. In this article, we present the results of high-resolution strain maps of a ferritic steel cantilever sample measured at different loads by both transmission and conventional diffraction modes, as well as strains in an austenitic steel compact-tension (CT) crack sample. The proof of principle experiments performed on the ENGIN-X beamline on a bent cantilever arrangement resulting in a uni-axial stress field verified that the strain values measured in diffraction and transmission mode are in good agreement. The characteristics of the transmission mode detector as well as the measured strain maps and future possibilities of this technology are discussed. [ABSTRACT FROM AUTHOR]

A deuterium–tritium base reaction pulsed neutron generator packaged in a flat computer chip shape of 1.54 cm (0.600 in) wide by 3.175 cm (1.25 in) long and 0.3 cm (0.120 in) thick has been successfully demonstrated to produce 10^3 neutrons per pulse (14 MeV) in a 0.5- \mu\s pulse. The neutron generator is based on a deuterium ion beam accelerated to impact a tritium-loaded target. The accelerating voltage is in the 15- to 20-kV range with a 3-mm (0.120 in) gap, and the ion beam is shaped by using a lens design to produce a flat ion beam that conforms to the flat rectangular target. The ion source is a simple surface-mounted deuterium-filled titanium film with a fused gap that operates at a current–voltage design to release the deuterium during a pulselength of about 1 \mu\s. We present some of the preliminary results and the general description of the working prototypes, which we have labeled the “NEUTRISTOR.” [ABSTRACT FROM PUBLISHER]