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This paper presents the experimental research of neutron induced single event upset (SEU) in Nano-SRAMs which was carried out in CSNS (China Spallation Neutron Source), CIAE (China institute of atomic energy) and XAPR (Xi’an pulsed reactor). The SEU cross section of Nano-SRAMs with four different feature sizes were measured. Experimental results indicated that the neutron induced SEU cross section were heavily dependent on the feature size of SRAM and the data pattern written to SRAM had little impact on the SEU cross section. We compared experimental results of white neutrons from CSNS to 2.5Mev, 14MeV neutrons from CIAE and reactor neutrons from XAPR. The comparison results showed that the neutron induced SEU cross section had a strong dependence on the energy of incident neutron. And the SEU cross section of Nano-SRAMs varies with different feature sizes obtained from different neutron sources has the same tendency.

This article presents a measurement of reaction rates for different reactions in NaCl samples which were irradiated by secondary neutrons from the spallation target. As target materials were used graphite and lead in two separate experiments. The reason for chloride salts utilization is their much lower price in contrast with fluoride salts. Salts are perspective material for cooling in 4th generation of fast reactors including Accelerator Driven System (ADS). The reaction rate measurement of reactions in NaCl is important for chloride salts utilization in ADS where is a quite different neutron spectrum beside fission reactors with a bigger component of high energy neutrons. The problem is that the experimental cross-sections of different possible reactions for those salts are not known therefore simulation could produce inaccurate results.

RF SplitBox is a 10-channel signal distribution module designed for use in LLRF control system of the European Spallation Source accelerator. It is designed in two variants, operating at different signal frequencies: 352.21 MHz and 704.42 MHz. The device is constructed from several submodules. Their design is discussed in this paper, with main focus on low-loss and low phase drift RF power splitter circuits. Low phase drift in signal distribution modules is essential for achieving and maintaining required beam parameters in the accelerator. RF SplitBox prototype measurement results are presented.

Hard rock destruction and comminution is directly linked with a high energy demand and high costs. Conventional tools are working against the compression strength of the rock. This results in an intense wear of the used tools due to the high forces needed to destroy hard rock. In times of scarcity of resources and climate change new technologies to destroy hard rock, more efficiently have to be developed. Besides other non-mechanical technologies, like flame jet drills, high pressure fluid jet, hydrothermal spallation and drilling high power laser [1], the Electric Impulse Technology represents an alternative procedure to destroy hard rock and conglomerates with less energy and power than conventional mechanical tools. An impulse voltage generator delivers fast rising high voltage impulses to break and weaken the material structure of the rock. This effect can be used, for example, for hard rock drilling and ore comminution. Advantages are, among others, the low forces, less wear and a reduced energy demand. The paper deals with the physical basics of the Electric Impulse Technology and its fields of application. Furthermore, the behavior of the used impulse voltage generators under changed conditions in comparison with conventional impulse voltage generators will be investigated.

The paper reports on a number of new physical phenomena found in the study of the laser radiation impact on porous materials. This applies to formation of laser plume at intensities significantly below the damage threshold of single crystal material which leads to the formation of needle-like structure with a diameter of ~1mm and a height of 8 mm on the target surface. The plume formation is characterized by irregular glow and spallation of the front surface of the target. In our opinion, these phenomena are caused by the transition from vapor to vapor-drop ablation, which leads to 6–8 times increase of the laser crater depth at the same energy of the laser pulse. At the same time, the vapor-drop mode of ablation is typical mainly for transparent materials, and the vapor mode is typical for materials that are opaque for laser radiation. Mathematical models explaining the reasons for the above processes and facts are presented.

A high efficiency klystron making use of second and third harmonic cavity bunching method (Core Stabilization Method) has been developed. This tube would be able to produce up to 1.5 MW of pulsed RF power at 704.42 MHz, and it is compatible with the requirements for the klystrons for the medium and high beta part of the linac of the European Spallation Source.

Neutron radiography is a non-destructive approach that has evolved in the last decades in contrast to the use of imaging facilities located in proximity of nuclear reactors and spallation sources. The majority of prior techniques exploit thermal neutrons by virtue of their relatively easy detectability, with there being less focus on fast-neutron imaging. In this research, we exploit fast neutrons emitted by a low-dose and mobile californium-252 source to perform fast neutron radiography. Simultaneously with neutrons, γ rays are also emitted by this particular isotope from spontaneous fission. The detector system used in our work affords the detection, real-time, of both fast neutrons and γ rays by means of pulse gradient analysis performed by a mixed field analyser. This retains event histories of both types of radiation, thus making possible to undertake, at the same time, neutron-, γ- and combined n-γ- radiography with the same field of view. The novelty of this technique is the use of a single radiation source and detection system that yields to two different radiographs of same object. In this particular record, we apply this technique to image a laptop battery, with the aim to highlight the presence of lithium ion polymer inside the battery’s cells. Our study shows how combined n-γ imaging is a valid alternative to X-rays imaging when there is the need to depict low-atomic number elements, as well as to discern elements with similar density. The system presented in this study is potentially applicable in safety & security inspection; for instance, it has the potential to be coupled with the advanced cabin baggage screening systems in airports, improving their detection performance.

We consider temperature stabilization of the phase-reference line at the European Spallation Source, a facility for neutron spallation currently under construction. Based on extensive modeling of the heat dynamics, a prototype model-based control system with associated hardware architecture is developed and experimentally evaluated on a small-scale setup. The results indicate that temperature stability within ±0.1°C is possible to achieve, also with significant disturbances in the ambient temperature expected during operation.

To achieve better process control and efficiency for high-temperature energy systems, it is essential to monitor the conditions (temperature, pressure) and structural health (mechanical integrity) of refractory materials used in the reactors, such as within coal slagging gasifiers. Therefore, there is a need for advanced sensors capable of operating under harsh environments reliably for extended time without degrading at high temperatures. The objective of this work was to investigate embedded temperature and spallation sensors within refractory ceramic brick to operate at temperatures >1200 °C. The key aspect of the proposed technology is that the solid-state sensors used for these applications are incorporated and interconnected within the volume of the refractory and would not result in extrinsic defects through the refractory. The current paper describes the testing of the electrical performance and chemical stability of the electroceramic composite composition at the application temperatures. The paper also discusses the performance of the embedded ceramic thermistor within the “smart bricks” at temperatures up to 1400 °C, with and without the presence of molten slag.

This article deals with the idea of using accelerator driven systems for thorium transmutation into the fissile material, which can be utilized in the accelerator driven systems and in thermal nuclear reactors. Thorium occurs on the Earth only in fertile isotope Th-232. It can be converted to fissile isotope U-233 by neutron capture and subsequent beta decay. The experimental part handles the data that were acquired by irradiation of four thorium samples in the field of secondary neutrons inside the QUINTA spallation set-up, which was irradiated by 660 MeV protons. Reaction rates for the different products were estimated using gamma-ray spectroscopy and activation techniques. Furthermore, Pa-233 production rates were also determined in all experimental samples. Pa-233 and fission production rates were calculated in all experimental samples using the MCNPX transport code and evaluated nuclear data for high-energy reactions. The experimental results are of a great importance for the future investigation of thorium in the accelerator driven system concept, validation of Monte Carlo-based calculation codes and validation of high-energy nuclear models.

Thermal heat production of spallation target describes the macroscopically current process in the observed object. Monitoring of temperature might reflect these process with some delay caused by heat transfer of its material and mainly its cover parts. Direct measurement of spallation target is usually not possible due to radiation safety. When uranium is used as a target it needs to be sealed (e.g. aluminum). According to all facts, it is known that results of temperature measurement experiments need to be carefully analyzed. The researched method is crucially depended on hardly estimated variables. Due to complicated geometry and changeable outer condition during experiments, the numerical model of Target Assembly QUINTA will be used to simulate all process from heat generation through its transfer to outer part to the temperature distribution. The global comparison of various methods with validation of thermal power production monitoring method by temperature will be discussed in the future paper. This paper is aimed at the description of the researched method, the process of measuring and discussion of data computed by MCNP6.1 simulation.

The experiments were performed with a spallation target QUINTA, which contains 512 kg of natural uranium in five sections. Threshold activation detectors of cobalt were placed in the whole volume of the target. The detectors were irradiated in the secondary neutron field generated by the 660 MeV proton beam. The first experiment was performed with the lead shielding around the target and the second one was carried out without shielding. The threshold activation detectors were measured and analyzed using the gamma-ray spectroscopy. The experimental results of reaction rates from the first experiment were compared with the second experiment.

There are several heavy materials used as neutron spallation targets. The purpose of this study is to optimize the geometry of the neutron production target in the spallation process. using Monte-Carlo method-Particle code MCNP-6. The simulation includes Uranium, Thorium, and Tantalum targets. We investigated the flux of neutron produced as well as the neutron axial distribution by variation the spallation target, target height and proton beam energy. The proton beams of a 2 cm radius were assumed uniformly distributed.

The European Spallation Source (ESS) aspires to be the worlds leading neutron source of the upcoming decades, and sets the scope on replacing 3 He tube detectors where it is reasonably achievable. The Multi-Grid detector, an Ar/CO 2 -filled proportional chamber based on solid 10B 4 C converter, is the most potent replacement technology for chopper spectroscopy. This study reproduces in a detailed Geant4 geometry of a neutron scattering instrument the data from the Multi-Grid demonstrator detector, that has been tested for a 1 year period, installed side-by-side to the 3 He tubes at the CNCS instrument at SNS. For the further understanding of the background of the detector, Monte-Carlo simulations were performed, with the ESS Coding Framework, using a Geant4 version extended with NXSG4 and NCrystal. A detailed and realistic model of the prototype was built and was validated via comparison against measured data. With this model, different sources of neutron scattering were determined and studied separately, providing a better understanding of the scattered neutron background. Due to these capabilities the model will be used in the further optimization of the detector, especially for the background reduction via shielding, which will lead to instruments with better signal-to-background ratio by design.

With the aim of providing critical nuclear data of primary knock-on atoms (PKAs) created from proton-induced spallation reactions, a new detection system was designed and dedicated to the PKA measurement that requires lower measurement threshold energies and superior mass resolution than the conventional experimental setups. Such requirements can be fulfilled by employing the TOF-E and dE-E methods, and this new PKA detection system, which consists of two fast timing detectors and one dE-E gas ionization detector. The design of the detectors and the experimental setup, along with the estimated system performed are briefly described in this paper.

Neutron imaging plays an essential role in the industrial applications, such as turbine blade manufacturing, fuel cell research, and nuclear fuel quality inspection. As isotopic neutron sources and neutron generators cannot provide highintensity neutron beams, and neutron beam lines of research reactors or spallation neutron sources are very scarce, a costeffective neutron source with high neutron yield and long lifespan should be researched. The e-LINAC driven photoneutron source, which converts X-rays to photoneutrons, has been proved to be a robust neutron source that can realize neutron yield ranging from 10$^{10}$ to 10$^{15}$ n/s. Hence it is a promising neutron source to provide neutron beams used for the neutron imaging. Because the e-LINAC works at a pulsed mode and the photoneutrons have a continuous energy spectrum, energy selective neutron imaging can thus be realized with the e-LINAC driven photoneutron source, with the aid of time of flight (TOF) technique. In this research, an e-LINAC driven photoneutron source is researched to strike the compromise between the neutron flux and the energy resolution. With a well-designed heavy water photon-to-neutron convertor, a 10 MeV/ 20 kW eLINAC can provide a thermal neutron flux of (7.28 × 10) $^{4}$n/cm$^{2}$ /s at 10 meters away from the electron target, with an energy resolution less than 20%. By using a low temperature (10K) moderator, the cold neutron flux at the same position can be (2.13 × 10) $^{4}$n/cm$^{2}$, and the energy resolution is less than 2%. This study may help realize the energy selective neutron imaging with an e-LINAC driven photoneutron source.

In this paper, the results of a 2.88 MW solid state long pulse modulator, which has been designed for the new linear collider at the european spallation source in Lund, are summarized. The presented modulator generates an output voltage pulse of 115 kV with a pulse length of 3.5 ms. The modulator design is verified by measurements performed with a full scale prototype, which is operated under nominal load conditions. All specifications are well within the given limits and the system achieves a pulse efficiency of 96.78% and an overall system efficiency of 91.88%.

Comparing with single beam klystron, Multi-Beam Klystron (MBK) can operate at low beam voltage, and has small volume and weight. To satisfy the requirement of high energy proton accelerator for Spallation Source and ADS (Accelerator Driven Sub-critical System), the design and calculation of a P-band 1.2MW MBK was made in Institute of Electronics, Chinese Academy of Sciences (IECAS). By using 30 beams, P-band MBK can work at beam voltage of 35 kV with cathode loading of

L-3 Electron Devices has successfully completed factory testing of the L6200 1.2 MW Multi-Beam Inductive Output Tube (MBIOT) for the European Spallation Source. The ten-beam, permanent magnet-focused device meets the maximum 1.2 MW output power specification at 704.42 MHz with a DC-to-RF efficiency of 68.4%; efficiency is maintained above 60% down to 650 kW. The gain at 1.2 MW exceeds 21 dB. No oscillations were detected at any point during operation. The MBIOT is currently being prepared for shipment, after which it will undergo long-duration life testing.

This work presents data obtained from an investigation into muon stimulated neutron emission in combination with the technique of muon scattering tomography. Initial measurements in lead of the neutron emission measured a half-life of 56.9 ± 6.63 ns which is three standard deviations lower than expected, with the error primarily attributed to prompt X-ray emission. A hypothetical detector, based on a muon scattering tomography prototype at AWE was used to examine the data expected from an integrated system. A lifetime 81 ± 3 ns was obtained here. Alongside this a portable muon trigger detector has been developed which aims to be implemented in a deployable muon scattering tomography system. The portable detector successfully measures muons to an accuracy of 20%.

The SoLid experiment aims to measure the anti-neutrino energy spectrum 5.5-10m from the core of the BR2 nuclear reactor at SCK•CEN in Mol, Belgium. The goal is to provide the most sensitive search for short-baseline neutrino oscillations and to resolve the reactor neutrino anomaly. In fact, the proposed detector technology will be very useful for anti-neutrino detection in other settings as well, such as nuclear safeguard and non-proliferation monitoring of nuclear reactors. The experiment utilizes a novel, highly segmented composite scintillator detector. The detector unit is based on 5 cm polyvinyl toluene scintillator cubes, thin neutron sensitive 6LiF:ZnS(Ag) sheets and a reflective Tyvek layer wrapping them for light tight. The first full-scale 288 kg detector prototype based on this technology was deployed at the BR2 reactor in November 2014. The main purpose was to study the capability of the detector design to discriminate background. Due to the low overburden and proximity to a nuclear reactor, efficient background reduction is crucial for a successful experiment. This work presents the advantages of the SoLid detector design for background reduction. The background components discussed in this proceeding are focused on the atmospheric and spallation neutrons induced by cosmic rays. The results are based on a full chain Geant4 based Monte Carlo simulations of the first full-scale SoLid prototype detector, and when applicable, also their comparison with measured data.

The European Spallation Source aspires to become the world's leading neutron source for the studies of materials during the next decade. At ESS 16 different instruments will be built. These instruments will require neutron beam monitors with high precision, low gamma sensitivity, high time and space resolution. Such neutron beam monitors are essential in various neutron experiments to continuously diagnose the delivered beam. In this work different types of neutron beam monitors from different suppliers have been characterized using the R2D2 beamline at IFE in Norway and using a Be-based neutron source. For the gamma sensitivity measurements different gamma sources have been used. The evaluation of these monitors includes the study of their efficiency, attenuation, uniformity, stability, and their sensitivity to gamma. In this work we report the results of this characterization.

The European Spallation Source (ESS) sets the scope on replacing 3He tube detectors where it is reasonably achievable, consequently advanced neutron detectors require a signal-to-noise (S/N) ratio high enough to be competitive with 3He tubes and satisfy scientific requirements. Advanced local shielding could provide the improved S/N. The objective of the current study is to create a tool that can be used during the shielding optimization process. The study is performed with Monte-Carlo simulations using a Geant4 version extended with NXSG4, that is capable to handle the crystal structure of specific materials, therefore the effects of neutron absorption, coherent and incoherent scattering were simulated. Validation of the extended Geant4 code, developed at ESS is also part of the current study by comparing the simulated results with analytical calculations. A detailed and realistic model of the state-of-the-art Multi-Grid detector has been implemented, as it is almost the only prototype with published data on scattering effects. Simulations were performed for appropriate shielding materials with various monoenergetic neutron beams. A robust tool has been developed that could be effectively used to arise the S/N via optimizing the detector shielding for specific setups and requirements for all inelastic instruments.

Recently we reported on a high efficiency, low gamma-sensitivity, high count rate capable 1D neutron detector consisting of ZnS:6LiF scintillator readout with WLS-fibers coupled to SiPMs which showed a performance comparable with a 3He-based detector. In this work we discuss a possible extension of the developed technology to large area 2D detectors with high count rate capability suitable, for example, for the new generation of neutron powder diffraction instruments planned at the European Spallation Source.

ESS, the European Spallation Source, will be a major user facility at which researchers from academia and industry will investigate scientific questions using neutron beams. ESS will deliver its protons to a solid, rotating tungsten target, which will in turn generate neutrons. A linear accelerator (Linac) creates protons at the ion source, accelerates them to an appropriate energy and steers them onto the target to create neutrons via the spallation process. Among the cryogenic accelerating sections, there are “warm” magnets for correcting the proton beam “optics”. This paper reports the chosen strategies for the power converters in these LWUs (Linac Warm Units). Amongst the power converters, we will highlight the 4-quadrant corrector magnets ones, based on a high precision and high bandwidth MOSFET H-bridge chopper, and a proposed novel topology for pulsed quadrupole magnets, instead of traditional DC ones. We will also demonstrate the interest of using pulsed magnets in place of DC ones in low duty-cycle Linacs, reducing the magnet losses and therefore the power consumption up-to 90%.

The use of 14 MeV neutron generators provides several strong advantages over spallation sources. This study aims at better defining the domain of applicability of this kind of facility for SEE characterization. Based on experiments using 14 MeV neutrons and white neutron beams on multiple devices (SRAM, SDRAM, FPGA), the irradiation data are then confronted with an analysis of the neutron nuclear recoils for the various ranges of energies. Finally, a simplified model is proposed to extrapolate 14 MeV neutron data to atmospheric environments.

Silicon is a promising anode material for lithium-ion battery application due to its high specific capacity. Unfortunately, silicon undergoes a volume expansion of 300∼400% full lithiation and suffers from severe capacity fade, which limit its successful application in commercial cells. In this study, we used in situ acoustic emission and laser microscope observation method for detecting the volume change in silicon negative electrodes. It was shown that the long-term performance of the silicon negative electrode was dictated by its spallation during the discharge steps, while only the first lithiation caused its delamination and spoliation in the charge step. This strongly indicates that the energy of emission, and hence the amount of damage, is related to capacity loss. This study demonstrate that AE is a powerful tool to survey the real-time mechanical damage and electrochemical degradation in the electrode.

Neutron flux is an important parameter for Accelerated Driven Systems. Density of the neutron flux is different in various positions inside a spallation target. The neutron flux can be obtained with the use of threshold activation detectors. An experiment with the spallation target made of 512 kg natural uranium and deuteron beam with energy 8 GeV was performed at the Joint Institute for Nuclear Research. Ten samples of Co-59 were irradiated of the secondary neutrons inside the spallation target at different positions. The reaction rates were determined by the gamma-ray spectroscopy with threshold activation detectors. The neutron flux was calculated by reaction rates. The experimental results were compared with Monte Carlo simulations.

L-3 Communications Electron Devices (L-3 EDD) is developing a high power Multi-beam IOT (MBIOT) for the European Spallation Source (ESS). Extensive simulation work has been completed and, where possible, results were validated against experiment using a scaled single-beam prototype. The MBIOT design has been finalized; fabrication of the tube is in progress, and configuration of a factory test bay is underway.

Diversified Technologies, Inc. (DTI), in partnership with SigmaPhi Electronics (SPE), has built three long pulse solid-state klystron transmitters to meet European Spallation Source (ESS) requirements. The prototype system was built under a DOE SBIR effort, and the first production modulators were built for, and installed at, CEA Saclay, Franc, and the National Institute of Nuclear and Particle Physics (IN2P3) in Orsay, France, where they will be used in support of RF component development and testing.

We describe the progress of the development of a multi-beam inductive output tube (MB-IOT) that will produce over 1.2 MW peak power at 704 MHz with over 65% efficiency. This is a collaborative effort between Thales Electron Devices (TED) and Communications & Power Industries (CPI) to design and fabricate a new RF source for the European Spallation Source (ESS). Main design features and predicted performance will be presented.

The European Spallation Source (ESS), currently under construction in Lund, Sweden, will house a suite of 16 user instruments for neutron scattering experiments. The spallation source of the ESS will emit relatively long, 2.8 ms, neutron pulses with an integrated flux that will greatly exceed that of current facilities. This leads to both large advancements in instrument performance as well as to increased length and complexity of the beam delivery systems. The instruments will each be equipped with neutron beam monitors used for data normalisation and analysis, as well as commissioning and diagnostics. In this paper we present the requirements for beam monitors for the ESS and the strategy to meet these in a standardised approach. A large range of specifications in efficiency, dynamic range, time and position resolution, compatible materials are needed. A new feature for neutron beam monitors for some locations, is the ability to measure time profile of each source pulse individually. In general, event mode readout will be used for monitors, similarly to other neutron detectors at the facility. A selection of detectors based on different technologies will be available. Monitors will be integrated with beam lines and choppers in a way that allows to freely choose the type of monitor based on final requirements of an instrument. For this end, space for a standardised module, housing a monitor will be provided in conjunction with chopper assemblies and elsewhere on each beam line.

L-3 Communications Electron Devices (L-3 EDD) has provided Inductive Output Tubes (IOTs) for the UHF television broadcast industry since 1998. More recently, we have produced a variety of high power versions specifically for accelerator applications, e.g., the 90 kW 500 MHz L-4444 for the NSLS-II at Brookhaven National Laboratory. L-3 EDD is now leveraging this expertise to develop a new super-power IOT for the European Spallation Source.

The European Spallation Source is a planned research facility in Lund-Sweden for scientific research using particle accelerators. In the facility protons will be accelerated in a pulsed pattern and collide with a heavy metal target. Due to the impact of the protons intense pulses of neutrons are emitted. These neutrons are led to experimental stations, where research on materials is executed. A total power of 25–40 MW will be needed when the beam is in operation. Because the linear accelerator beams the protons in a 14 Hz pulse pattern flicker and other distortion may impact on the transmission grid. In the following paper the focus lies on converters and control design to lower the grid impact. The internal grid is analyzed to improve the availability. Finally ac- and dc-distribution grids are compared.

Monte Carlo CASCADE version 2004 code is used to simulate the neutron flux inside IAEA benchmark ADS design of a 1500 MW th reactor. The reactor is found to have the capability of production of the said amount of thermal energy and has high left over neutron fluence. This n - fluence is equivalent to that of a critical reactor for a given input fuel. Incineration reactions of long lived fission products and long lived trans-uranic actinides are discussed and it is inferred that element like plutonium (239) may be degraded directly in the spallation neutrons close to the spallation target and Low Life Fission Product (LLFP) may better be degraded at later positions where highly thermalized neutrons are available. This stresses upon necessity of producing of an ADS design that accommodates these observations. In any condition, to obtain both energy and possibility of transmutation of the waste, ADS need to operate at criticality (k eff < 0.98).

An alternative detector design for Small Angle Neutron Scattering (SANS) applications is currently under development at the European Spallation Source (ESS). Given the unavailability and high price of 3He, this detector design utilizes gaseous detectors with 10B as neutron converter and is ideally suited for a SANS instrument at the ESS. The novel aspects of the geometry, exploiting the properties of the converting material, in combination with the performance of the detector are addressed by means of analytical calculations, as well as detailed Monte Carlo simulations using a customized version of Geant4. Last but not least, the progress on the conceptual prototype design is presented.

This paper reports enhancement effect of N2/O2 gas addition in thermal plasma irradiation on the spallation phenomena from polyamide-66 (PA66) specimens with water absorption. The polyamide materials are widely used, for example, in low-voltage circuit breakers and arcing horns as ablation material. In such devices, the polymer is often contacted with arc discharges to be ablated, which increases the arc current interruption ability of the circuit breakers. In our previous experiments, not only ablation but also spallation phenomena had been found to occur from PA66 specimens with water absorption by Ar thermal plasma irradiation. The present work was conducted to investigate effect of N2/O2 inclusion in the irradiating thermal plasma on the occurrence of spallation phenomena because the air circuit breaker was used in air. Relative oxygen admixture ratio to N2 was changed from 0% to 100% with a fixed heat flux irradiated to PA66 specimens. Results indicated that O2 inclusion effectively promotes the frequency of spallation particle ejection from PA66 specimen with 3 wt% water absorption.

Monte-Carlo simulations of spallation fields are used to determine neutron and gamma spectra in beams used for single-event-effects testing. Spectra at LANSCE (ICE House) and TSL (ANITA) are calculated using Geant4 with Bertini and binary intranuclear cascade (INC) models. Results with the binary INC model give a good representation of neutron spectra obtained from measurements and independent calculations in each case, and predict gamma dose rates consistent with measured data where these are available. The gamma field in each beam is dominated by a continuum between about 100 keV and about 10 MeV. Integral gamma yields are approximately 0.26 γ p−1 sr−1 and 0.046γ p−1 sr−1 at the ICE House and ANITA, respectively.

The world fusion programme needs within next two decades the results of two large facilities in the race towards commercial fusion power plants based on plasma magnetic confinement. ITER, presently under construction in the South of France will teach us how to control stable deuterium-tritium nuclear fusion reactions. In turn, IFMIF will allow the qualification and characterization of the materials for the first wall of the reactor vessel. The first wall, a combination of layers of different specialized materials that aims to maximize the conversion of neutrons into thermal energy and breed tritium to fuel the fusion reactions, must be capable to withstand structural damage of up to 150 displacements per atom in the metal lattice of purposely designed RAFM (Reduced Activation Ferritic-Martensitic) steels. The 14.1 MeV energy of fusion neutrons makes existing neutron sources (namely fission reactors and spallation facilities) not fully suitable to reproduce experimentally the degradation of mechanical properties of the candidate materials. IFMIF will generate a neutron flux of 1018/m2·s with a broad energy peak at around 14 MeV through (d, Li)n stripping reactions. Two deuteron accelerators with 125 mA, 40 MeV beams and a footprint of 20 cm × 5 cm will impact a liquid Lithium screen flowing at 15 m/s. The neutrons generated will irradiate test modules at different levels of neutron fluxes. Of particular relevance will be the 0.5 l of the High Flux Test Module where miniaturised specimens, presently under qualification, will be tested at various controlled temperatures to reach within a few years the same conditions as the first wall of a commercial reactor vessel. IFMIF, presently in its Engineering Validation and Engineering Design Activities (EVEDA) phase, is overcoming the technical challenges with three main prototyping activities: 1) the world largest liquid Lithium loop, presently under operation in Oarai (Japan); 2) different prototypes of the High Flux Test Module and its cooling loop to independently control the testing temperature in Karlsruhe (Germany) and 3) a deuteron Linac at 125 mA and 9 MeV, which installation starts in March 2013 in Rokkasho (Japan).

The 5 MW European Spallation Source, currently in its design phase, includes a linear proton accelerator sending a 2.86 ms long pulse of 2 GeV protons at 14 Hz to a tungsten target. This spallation source distributes thermal and cold neutron beams to a large variety of state-of-the-art neutron instruments, supported by a suite of laboratories and a supercomputing data management and software development center. The target is a rotating wheel 2.5 m in diameter composed of helium cooled tungsten plates and produces high intensity gamma and fast neutron pulses (higher than 2E15 n/cm2/s). This paper focuses on the design of 2 types of instrumentation: to monitor target operation and to control the proton beam parameters. Instrumentation mounted on the rotating target (designed for a minimum lifetime of 5 years) to monitor the helium coolant flow and the evolution of irradiated tungsten plates and the target vessel, the target balance, vibrations and displacement is presented as well as a dedicated instrumentation plug installed at opposite the impinging proton beam, which will monitor the target wheel with an LDV and an infra-red camera and perform gamma scanning during and after irradiation. Upstream of the target, a suite of instrumentation will monitor the properties of the 2 GeV proton beam. This suite will consist of imaging devices and multi-wire grids to monitor the beam density distribution at the proton beam window and at the target. An additional imaging system will observe luminescence from the Helium gas between the proton beam window and the target. Beam halo will be monitored by thermocouples located near the edge of the aperture. Further upstream, electromagnetic pickups will measure the beam centroid position, the beam current, and the beam pulse's time of arrival. This time-of-arrival signal will allow precise synchronization of the target's rotation and the beam pulse structure.

Diversified Technologies Inc. (DTI) is developing a long-pulse modulator which meets the requirements of the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory and the European Spallation Source (ESS). The modulators will deliver pulses at up to 100 kV and 50 A with a pulse width of 3.5 ms and a droop much less than 1%. The modulator will be delivered to SNS for conditioning klystron tubes.

The European Spallation Source (ESS) requires 5 MW of proton beam power which is a factor of five larger in power compared to existing spallation facilities. To accommodate the high power, the ESS facility will pioneer the long pulse concept. The proton linac sourcing the neutron spallation target will be a 2 GeV superconducting linac that requires 125 MW of peak RF power at 704 MHz.

Innovative in situ Environmental Scanning Electron Microscope (ESEM) hot stage metrology was developed to understand packaging process and failure mechanisms through elevated temperature. For solder thermal interface materials (STIM), AuIn2 intermetallic compound (IMC) spallation during indium melting is proposed to explain its formation mechanism correlated to STIM thermal degradation. For the first time, AuIn2 IMC spallation is validated by direct observation of its dynamic behavior at elevated temperature using in situ ESEM hot stage metrology. In situ ESEM hot stage study also demonstrates that package dynamic warpage is a key contributor for corner delamination of polymer thermal interface materials (PTIM). It is found that the force applied with heatsink at the platform level helps to alleviate the risk of PTIM delamination. Application of in situ ESEM hot stage metrology to predicting package thermal performance and understanding package dynamic warpage induced failures are discussed.

We investigate an impact of parasitic bipolar action on 28nm sequential elements in the terrestrial environment through spallation neutron beam irradiation tests. We discuss the contribution of parasitic bipolar action to the technology trend of SER through neutron tests on Flip-Flops and SRAMs.

The European Spallation Source (ESS) in Lund, Sweden will become the world's leading neutron source for the study of materials by 2025. First neutrons will be produced in 2019. It will be a long pulse source, with an average beam power of 5 MW delivered to the target station. The pulse length will be 2.86 ms and the repetition rate 14 Hz. The ESS is presently in a design update phase, which ends in February 2013 with a Technical Design Report (TDR). Construction will subsequently start with the goal of bringing the first seven instruments into operation in 2019 at the same time as the source. The full baseline suite of 22 instruments will be brought online by 2025. These instruments present numerous challenges for detector technology in the absence of the availability of Helium-3, which is the default choice for detectors for instruments built until today. Additionally a new generation of source requires a new generation of detector technologies to fully exploit the opportunities that this source provides. This contribution presents briefly the current status of the ESS, and outlines the timeline to completion. The number of instruments and the framework for the decisions on which instruments should be built are shown. For a conjectured full instrument suite, which has been chosen for demonstration purposes for the TDR, a snapshot of the current expected detector requirements is presented. An outline as to how some of these requirements might be tackled is shown. Given that the delivery of the ESS TDR is only a few months away, this contribution reflects strongly the content of the TDR.

Summary form only given. Neutrons are a unique tool to alter and diagnose material properties and excite nuclear reactions with a large field of applications. It has been stated over the last years, that there is a growing need for intense, pulsed neutron sources, either fast or moderated neutrons for the scientific community. Accelerator based spallation sources provide unprecedented neutron fluxes, but could be complemented by novel sources with higher peak brightness that are more compact. Lasers offer the prospect of generating a very compact neutron source of high peak brightness that could be linked to other facilities more easily.

Parasitic bipolar effects are intentionally used to prevent a simultaneous flip of redundant FFs, which make them more fault-resilient to soft errors. Device simulations reveal that a simultaneous flip of redundant latches is suppressed by storing the opposite values instead of storing the same value due to its asymmetrical structure. The state of latches always becomes a specific value after a particle hit due to the bipolar effects. Spallation neutron irradiation proves that no MCU is observed in the D-FF arrays in which the stored values of latches are equivalent to the specific value. The redundant latch structure storing the opposite values is robust to the simultaneous flip.

Investigation of fission after electromagnetic excitation and spallation requires to unambiguously identifying all particles produced during the processes. Identification of the nuclear charge of the fission fragments is attributed to a Multi-Sampling Ionization chamber (MUSIC) with minimized thickness. The detector design and first results obtained during in-beam experiments are presented.

Dynamics behavior of the spallation particles ejected from polyamide was investigated both by experimental and numerical approaches. Polymer materials are widely used for gas flow nozzle in low-voltage or high-voltage circuit breakers. Effective utilization of such polymer ablation is expected to enhance the arc interrupting capability of the circuit breaker. In the experiment, the Ar induction thermal plasma was directly irradiated to polymer material such as polytetrafluoroethylene (PTFE), polyamide-66 (PA66) and polyamide-6 (PA6) fundamentally to study the interaction between the thermal plasma and the polymers. As a result, we found out that not only ablated vapor but also spallation particles were ejected from the polyamide materials surface from the experiment. A numerical model was developed on the behavior of spallation particles. Initial kinetic energy of spallation particles was estimated by numerical approaches.