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The radial neutron camera (RNC) is a key ITER diagnostic system designed to measure the uncollided 14- and 2.5-MeV neutrons from deuterium-tritium (DT) and deuterium-deuterium (DD) fusion reactions, through an array of detectors covering a full poloidal plasma section along collimated lines of sight (LoS). Its main objective is the assessment of the neutron emissivity/alpha source profile and the total neutron source strength, providing spatially resolved measurements of several parameters needed for fusion power estimation, plasma control, and plasma physics studies. The present RNC layout is composed of two fan-shaped collimating structures viewing the plasma radially through vertical slots in the diagnostic shielding module (DSM) of ITER Equatorial Port 1 (EP01): the ex-port subsystem and the in-port one. The ex-port subsystem, devoted to the plasma core coverage, extends from the Port Interspace to the Bioshield Plug: it consists of a massive shielding unit hosting two sets of collimators lying on different toroidal planes, leading to a total of 16 interleaved LoS. The in-port system consists of a cassette, integrated inside the port plug DSM, containing two detectors per each of the six LoS looking at the plasma edges. The in-port system must guarantee the required measurement performances in critical operating conditions in terms of high radiation levels, given its proximity to the plasma neutron source. This article presents an updated neutronic analysis based on the latest design of the in-port system and port plug. It has been performed by means of the Monte Carlo MCNP code and provides nuclear loads on the in-port RNC during normal operating conditions (NOC) and inputs for the measurement performance analysis.

A calibration procedure is proposed for ITER Radial Neutron Camera that relies on embedded sources, reference ITER pulses and cross-calibration with ITER fission chambers and activation system coupled to Monte Carlo simulations of radiation transport. The proposed procedure would allow to measure the neutron emissivity profile and of the fusion power with 10 % accuracy and precision, a time resolution of 10 ms and a spatial resolution of a/10 for ITER entire life-time.

The ITER Radial Neutron Camera (RNC) is a multichannel detection system hosted in the Equatorial Port Plug 1 (EPP 1). It is designed to measure the uncollided neutron flux from the plasma, providing information on the neutron emissivity profile and total strength. The RNC structure consists of two sub-systems based on fan-shaped arrays of cylindrical collimators: the ex-port system, covering the plasma core with 2 sets of lines of sight lying on different toroidal planes, and the in-port system, enclosed in a dedicated cassette within the EPP1 diagnostic shielding module, for the measurement of neutrons generated in the plasma edge. Due to the harsh environment in which it has to operate, the design of the in-port RNC system is particularly critical both from the measurements point of view (low signal to noise ratio induced by the high level of scattered neutrons at the detector positions) and from the structural point of view. The paper presents the results of the neutronic analyses performed with the MCNP Monte Carlo code with the aim of optimizing the in-port RNC design in order to enhance the diagnostic measurement performance and evaluating the nuclear loads that have to be withstand by its structural elements, detectors and associated components.

The main goal of the ITER Radial Neutron Camera (RNC) is to provide the plasma neutron emission profile (neutron emissivity) through measurement of the uncollided 14 MeV and 2.5 MeV neutrons from deuterium-tritium (DT) and deuterium-deuterium (DD) fusion reactions. The system is based on an array of detectors (diamonds are among the candidate detectors) located in collimated lines of sight (LOS) viewing the plasma through the ITER Equatorial Port Plug #1. Tomographic reconstruction techniques are used to calculate the neutron emissivity. The contribution of random noise on diamond detector pulses to the count rate uncertainty is investigated in this paper. The energy spectrum of the neutrons impinging on the detector has been calculated by means of MCNP calculations for one line of sight of the RNC In-Port system. The spectrum has been convoluted with the diamond detector response functions and the Pulse Height Spectrum (PHS) has been obtained. Experiments have been carried out with the CAEN™ 5810D detector emulator, that is able to produce arbitrary pulse height distributions as those expected in the ITER RNC. Random noise has been added on each detector pulse of the distribution using the detector emulator. The resulting uncertainty produced on the count rate has been evaluated as a function of the random noise level.

The ITER Radial Neutron Camera is a diagnostic whose objective is measuring neutron emissivity and fusion power density through an array of detectors placed in collimating structures. The RNC is composed of two subsystems (In-Port RNC and Ex-Port RNC), located in the Equatorial Port 01 of the ITER tokamak. Although the measurements from the RNC are required for ITER D -T phase, its In-Port components must be ready for Assembly phase 2. Consequently, the two subsystems will be delivered at different times. At the current status of the design the In-Port RNC interfaces must be defined, if not fully specified, in order to allow for the subsystem integration in the Port Plug. A thorough assessment of the interfaces of the subsystem with all the diagnostics, plants and services in the port has been made, taking into account the concurrent development of the Equatorial Port 01 and the progress in the design of some of the subsystem components that may affect the identification of interfacing Plant Systems. This paper deals with the process that led to definition of the internal and external interfaces of the In-Port RNC, highlighting the main issues and the solutions adopted to perform integration within the Equatorial Port Plug 01.

Neutron/gamma discrimination techniques are widely applied in scintillator-based neutron diagnostics for present nuclear fusion tokamak experiments (e.g. JET – Neutron Camera and compact neutron spectrometer) and will also be necessary for neutron diagnostics of up-coming machines (e.g. ITER Radial Neutron Camera). Neutron/gamma discrimination in scintillators relies on the fact that the detectors output pulses have different shapes depending on the impinging particle; several discrimination techniques are described in literature such as the charge-integration, curve-fitting and pattern recognition [1]. This paper aims at describing a new technique for neutron/gamma discrimination in scintillators based on trapezoidal filtering, which targets Field Programmable Gate Array (FPGA) implementation due to its recursive nature. Furthermore its capability to restore the baseline of each detected pulse and the fact that the output signals are shorter than the correspondent incoming pulses, points this technique as a promising solution for applications in high count rate conditions. First results coming from the application of a real-time FPGA implementation of the trapezoidal filter to simulated neutron/gamma data including pile-up events and to real scintillator data will be presented.

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). © 1973-2012 IEEE.

The Radial Neutron Camera (RNC) of ITER (International Thermonuclear Experimental Reactor) is a multichannel detection system designed to measure the uncollided neutron flux from the fusion plasma , providing information on the neutron emissivity profiles and source strength. Fission chambers and diamond detectors are candidate detectors for the RNC In-port subsystem. This is a high radiation environment (up to ∼ 5 MGy gamma dose and ∼ 2 × 10 16 n/cm2 neutron fluence) where about 500 baking cycles up to 240 °C are foreseen over the whole ITER lifetime. In order to assess the feasibility of using diamond detectors in such harsh conditions, and to study the best technological solutions, we are currently performing a set of tests to understand the behavior of diamond detectors under radiation and thermal stresses: (1) thermal stress tests at constant temperature of 240 °C and thermal cycling between 100 °C and 240 °C; (2) gamma-hardness test up to a total dose of 4.7 MGy; (3) neutron-hardness test (limited to 2 × 10 14 n/cm2 in this work).

Single Crystal Diamonds (sCD) have been selected as neutron detectors for the ITER Radial Neutron Camera (RNC). This paper investigates experimentally the hardness of these detectors to 14 MeV neutrons in order to have indications of their limits of applicability in the RNC. The experiment has been performed at the Frascati Neutron Generator (FNG) facility using three sCDs of different thickness ( 500 , 300 , 100 μ m ). The degradation of the sCD Charge Collection Efficiency (CCE) with increasing 14 MeV neutron fluence has been found to be lower with decreasing sCD thickness. Strong polarization effects produced by the trapping of charge carriers in the defects produced by the neutron irradiation are observed already at about 4 ⋅ 1 0 14 n ∕ cm 2 in the 100 μ m thick sCD. A software correction of the polarization effect is proposed, which enables to extend the sCD range of operation up to higher fluences. Taking into account such correction, a 50 μ m thick sCD is expected to reach 1 0 15 n ∕ cm 2 with a CCE greater than 0.7.

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.

The Radial Neutron Camera (RNC) diagnostic is a neutron detection system with multiple collimators aiming at characterizing the neutron emission that will be produced by the ITER tokamak. The RNC plays a primary role for basic and advanced plasma control measurements and acts as backup for system machine protection measurements. During the RNC system level design phase the following real-time data processing algorithms were developed to assess RNC data throughput needs and measurement performances: (i) real-time data compression block (ii) real-time calculation of the neutron emissivity radial profile, based on Tikhonov regularization, starting from the line-integrated measurements, the line-of-sight geometry and using the magnetic flux information [1] (iii) real-time calculation of the neutron emissivity profile using a-priori trained neural networks, the line-integrated measurements and the magnetic flux information (the best output from different neural networks being evaluated by a figure of merit that maps the neutron emissivity profile to the original line-integrated measurements) [2] . This paper presents results for the processing times of the various algorithms and their minimum control cycle for different conditions, such as number of lines of sight, number of magnetic flux surfaces and measurement error on the line integrated RNC measurements.

The ITER Radial Neutron Camera (RNC) is a neutron diagnostic intended for the measurement of the neutron emissivity radial profile and the estimate of the total fusion power. This paper presents a proof-of-principle method based on neural networks to estimate the neutron emissivity profile in different ITER scenarios and for different RNC architectures. The design, optimization and training of the implemented neural network is presented together with a decision algorithm to select, among the multiple trained neural networks, which one provides the inverted neutron emissivity profile closest to the input one. Examples are given for a selection of ITER scenarios and RNC architectures. The results from this study indicate that neural networks for the neutron emissivity recognition in ITER can achieve an accuracy and precision within the spatial and temporal requirements set by ITER for such a diagnostic.

The ITER Radial Neutron Camera (RNC) is a multichannel detection system hosted in the Equatorial Port Plug 1 (EPP 1) designed to provide information on the neutron source total strength and emissivity profiles. It consists of two sub-systems: the ex-port line-of-sights (LOSs), covering the plasma core, embedded in a massive shielding block located in the Port Interspace, and the in-port LOSs distributed in two removable cassettes integrated inside the Port Plug. Presently, the RNC layout development process is undergoing a System Level Design phase: several preliminary architectural options based on a System Engineering work have been defined: a detailed nuclear analysis of these options has been performed through radiation transport calculations with the MCNP Monte Carlo code. The radiation environment at the detectors positions has been fully characterized through the evaluation of the expected neutron spectra and the secondary gamma background and the analysis of the 3D radiation maps. Moreover, the impact of a reduced ex-port shielding block on the neutron and gamma spectra has been investigated. The results of the present study provide guidelines for the development of the RNC final design and the necessary data for the measurement performance analysis.

The present paper describes the architecture and the performances of a diamond detector data acquisition system based on PXIexpress (one of the standards suggested by ITER). Performances have been evaluated by feeding the digital acquisition system with pulses generated by a digital detector emulator replicating the shape and energy distribution expected for a Single Crystal Diamonds (sCD) neutron detector in deuterium-tritium plasmas.

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

Three-dimensional neutronics, activation and shutdown dose rate analyses were performed with MCNP5 Monte Carlo code, FISPACT-II inventory code and Advanced D1S dynamic tool for the design and licensing of Divertor Tokamak Test facility (DTT). Advanced shielding concepts and mitigation strategies have been studied to guarantee sufficient protection of the superconducting coils and to reduce the streaming and the neutron-induced radioactivity. The present nuclear design study provides main outcomes for the loads assessment, shielding and materials requirements and on maintenance strategy and storage of activated components.

The general features of a 4He gas scintillator prototype detector were characterized, as an alternative to liquid and plastic scintillators for a potential integration into the Radial Neutron Camera (RNC) in ITER. Two measurement campaigns were conducted at the Physikalisch-Technische Bundesanstalt (PTB) Ion Accelerator Facility (PIAF) in Germany using fast mono-energetic neutrons. Results from the first measurement campaign showed a light output response of the detector linear with the incident neutron energy, at least up to 14.8 MeV. A complete discrimination between neutrons and gammas was achieved by applying a 0.30 MeV threshold in terms of deposited neutron energy. The response function and the intrinsic efficiency of the detector were characterized in a second measurement campaign using collimated-beam conditions, similar to those expected in the RNC at ITER, to test the suitability of the detector in such a diagnostic system. The response function to 2.5 MeV and 14.8 MeV mono-energetic neutrons was measured and validated by Monte Carlo simulations. Some changes to the present prototype may be considered in the future to make it suitable as a neutron detector for the RNC at ITER.

The purpose of the ITER Radial Neutron Camera (RNC) is the measurement of the plasma neutron emissivity profile [neutrons∙s−1 m-3] for burn control purposes. The present RNC design consists of 22 collimated detector systems providing a set of line-integrated neutron measurements [neutrons∙s−1 m-2] with full coverage of the plasma poloidal cross-section; the neutron emissivity can be recovered from the line-integrated measurements by means of dedicated reconstruction techniques (1D spatial inversion, 2D tomography). The present paper focuses on the evaluation of the improvement in the RNC 2D reconstruction of the neutron emissivity obtained by using the total neutron yield value provided by an independent diagnostic as additional constraint in the tomography procedure. The analysis was performed using a tomography code based on the Minimum Fisher Regularization (MFR). A clear improvement of the neutron emissivity reconstruction has been observed when the total neutron yield constraint is considered. The improvement is seen in: extension of the spatial region in which the accuracy of the reconstruction is better than 10 %; better reconstruction of peaked emissivity profiles; and robustness against measurements noise and line of sight data loss.

Single Crystal Diamond (sCD) are candidate neutron detectors for the ITER Radial Neutron Camera (RNC) due to their capability of performing both neutron counting and spectroscopy while withstanding high levels of radiation. This paper presents a study on methods of separation between neutron and gamma events, through the analysis of the pulse shapes of a 500 μ m thick sCD. Methods for gamma rejection may be beneficial especially during ITER deuterium–deuterium operation to extract the 2.5 MeV neutron signal. Four neutron/gamma separation algorithms for sCD neutron detectors are presented. Three algorithms rely on pulses shape information and one on the frequency analysis. The final experimental implementation based on multi-step separation approach achieved above 90% of correctly discriminated pulses.

The Divertor Tokamak Test (DTT) facility, whose design phase is currently under finalization, is an Italian project aimed to investigate alternative power exhaust solutions for DEMO. It is designed to operate with significant power loads and enough flexibility to test innovative divertor configurations, different plasma edge and bulk conditions approaching, as much as possible, those planned for DEMO. Among the neutron diagnostics, a multi-channel neutron camera, most likely equipped with the liquid scintillators NE213, is foreseen to provide spatially resolved measurements of several plasma parameters needed for fusion power estimation, plasma control and plasma physics studies. This paper presents a preliminary study performed in support of the DTT neutron camera design. A detailed MCNP model representing a 20° sector of the machine integrating its main components and detectors assemblies has been developed and used for this study. Three-dimensional neutron transport simulations have been carried out by means of the MCNP Monte Carlo code coupled with the FENDL nuclear data libraries. The diagnostic design was optimized starting from the assessment of the expected detector performances obtained by using the calculated neutron fluxes and spectra and the NE213 response functions. The outcomes of this analysis provide the detectors requirements and guidelines for the development of the above-mentioned diagnostics, investigating its feasibility and suitability with the neutron emissivity foreseen for the DTT operational scenarios.

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.

To achieve the aim of the ITER Radial Neutron Camera Diagnostic, the data acquisition prototype must be compliant with a sustained 2 MHz peak event for each channel with 128 samples of 16 bits per event. The data is acquired and processed using an IPFN FPGA Mezzanine Card (FMC-AD2-1600) with 2 digitizer channels of 12-bit resolution and a sampling rate up to 1.6 GSamples/s mounted in a PCIe evaluation board from Xilinx (KC705) installed in the host PC. The acquired data in the event-based data-path is streamed to the host through the PCIe x8 Direct Memory Access (DMA) with a maximum data throughput per channel is 0.5 GB/s of raw data (event base), 1 GB/s per digitizer and up to 1.6 GB/s in continuous mode. The prototype architecture comprises an host PC with two KC705 modules and four channels, producing up to 2 GB/s in event mode and up to 3.2 GB/s in continuous mode. To reduce the produced data throughput from host to ITER databases, the real-time data compression was evaluated using the LZ4 lossless compression algorithm, which provides compression speed up to 400 MB/s per core. This paper presents the architecture, implementation and test of the parallel real-time data compression system running in multiple isolated cores. The average space saving and the performance results for long term acquisitions up to 30 minutes, using different data block size and different number of CPUs, is also presented., 21st Real Time Conference, June 9th - 15th, Colonial Williamsburg, Virginia, United States

The neutron detection system for characterization of emissivity in ITER Tokamak during DD and DT experiments poses serious challenges to the performance of the diagnostic control and data acquisition system (CDAcq). The ongoing design of the ITER Radial Neutron Camera (RNC) diagnostic is composed by 26 lines of sight (LOS) for complete plasma inspection. The CDAcq system aims at meeting the ITER requirements of delivering the measurement of the real-time neutron emissivity profile with time resolution and control cycle time of 10 ms at peak event rate of 2 MEvents/s per LOS. This measurement demands the generation of the neutron spectra for each LOS with neutron/gamma discrimination and pile up rejection. The neutron spectra can be totally processed in the host CPU or it can use the processed data coming from the system FPGA. The number of neutron counts extracted from the spectra is then used to calculate the neutron emissivity profile using an inversion algorithm. Moreover, it is required that the event based raw data acquired is made available to the ITER data network without local data storage for post processing. The data production for the 2 MEvents/s rate can go up to a maximum data throughput of 0.5 GB/s per channel. The evaluation of the use of real-time data compression techniques in RNC is also depicted in another contribution. To meet the demands of the project a CDAcq prototype has been used to design and test a high-performance distributed software architecture taking advantage of multi-core CPU technology capable of coping with the requirements. This submission depicts the design of the real-time architecture, the spectra algorithms (pulse height analysis, neutron/gamma discrimination and pile-up correction) and the inversion algorithm to calculate the emissivity profile. Preliminary tests to evaluate the system performance with synthetic data are presented., Comment: Conference Record - 21st IEEE Real Time Conference, Colonial Williamsburg, USA, 9-15 June 2018

The ITER Radial Neutron Camera (RNC) Data Acquisition (DAQ) prototype is based on the PCIe protocol as the interface to be used between the I/O unit and the host computer, allowing the scalability of the final RNC DAQ system. The prototype architecture comprises two digitizer modules with two channels in each, installed in the host computer and the maximum produced data throughput is up to 1.6 GB/s per board, allowing a sustainable 2 MHz peak event to cope with the long plasma discharges, up to half an hour. The Linux Device Driver provides the interface between the hardware and the host applications running on a high-performance computer, which receives the acquired data through the Direct Memory Access (DMA) channels. The preliminary tests show that the Linux kernel miss some hardware interrupts when the time between interrupts is in the microsecond scale, which implies data loss if a traditional read technique based on interrupt handling is implemented. The direct usage of the polling mechanisms to retrieve the data is not suitable as the variable event rate over the same discharge does not allow to define an optimal fixed-time to retrieve data and identify missing data packets. This contribution presents the architecture, implementation and test of a different device driver approach using the polling mechanism which improves the performance and reliability. This allows the device driver to automatically check and transfer missing data blocks, recovering the data losses transparently for the host applications. The performance results for tests with different event data rates and duration up to an hour are also presented.

A digital upgrade of the analogue electronics of the Frascati Tokamak Upgrade (FTU) neutron camera was carried out in order to enable studies on runaway electrons by measuring the hard X-rays produced in the bremsstrahlung interactions between runaway electrons and plasma ions. This "gamma camera" system is based on six radial lines of sight equipped with liquid organic scintillators capable of neutron/gamma discrimination. The digital acquisition system is composed by three digitizers (14-bit, 400 Msamples/s) enabling the separation between neutron and hard X-ray events also in conditions of very high count rate (MHz range). The first measurement results indicate the capability of the diagnostic to provide HXR profiles for energies >0.1 MeV and information on the runaway population during the Ip ramp-up, flattop and ramp-down phases. Disruption events can also be analyzed with sub-millisecond time resolution, although in such phases the data are affected (mainly in the inner three detectors) by the presence of a strong HXR background not originating in the plasma. © 2015 Published by Elsevier B.V.

The main role of the ITER Radial Neutron Camera (RNC) diagnostic is to measure in real-time the plasma neutron emissivity profile at high peak count rates for a time duration up to 500 s. Due to the unprecedented high performance conditions and after the identification of critical problems, a set of activities have been selected, focused on the development of high priority prototypes, capable to deliver answers to those problems before the final RNC design. This paper presents one of the selected activities: the design, development and testing of a dedicated FPGA code for the RNC Data Acquisition prototype. The FPGA code aims to acquire, process and store in real-time the neutron and gamma pulses from the detectors located in collimated lines of sight viewing a poloidal plasma section from the ITER Equatorial Port Plug 1. The hardware platform used was an evaluation board from Xilinx (KC705) carrying an IPFN FPGA Mezzanine Card (FMC-AD2-1600) with 2 digitizer channels of 12-bit resolution sampling up to 1.6 GSamples/s. The code performs the proper input signal conditioning using a down-sampled configuration to 400 MSamples/s, apply dedicated algorithms for pulse detection, filtering and pileup detection, and includes two distinct data paths operating simultaneously: i) the event-based data-path for pulse storage; and ii) the real-time processing, with dedicated algorithms for pulse shape discrimination and pulse height spectra. For continuous data throughput both data-paths are streamed to the host through two distinct PCIe x8 Direct Memory Access (DMA) channels., Comment: 6 pages, 10 figures, 21st IEEE Real Time Conference (RT-2018), Colonial Williamsburg, 9-15 June 2018

A set of gamma ray spectrometers has been designed for ITER within the Radial Gamma Ray Spectrometer (RGRS) project. The aim of this project is designing a system, integrated with the ITER radial neutron camera, which is able to measure the gamma-rays emitted from the plasma with a good energy resolution (about 1.5% at 4.44 MeV) and at high counting rates (in excess of 1 MHz). The RGRS will be able to operate both in the D phase and in the full-power DT phase and will measure gamma rays from (i) reactions between fast ions, such as particles, and light impurities and (ii) bremsstrahlung emission generated by runaway electron interactions with both plasma bulk and tokamak walls. The RGRS detectors are arranged in nine lines of sights (able to cover a radial region with r < a/3), each featuring a large LaBr3 scintillator crystal. Due to the high neutron flux and magnetic field, several solutions have been adopted to guarantee a good signal to background ratio and MHz counting rate capabilities. The RGRS is capable to combine space and energy distribution measurements of particles and runaway electrons, which will help the study of the fast particle physics in a burning plasma. Published by AIP Publishing. https://doi.org/10.1063/1.5038963

System engineering is an established methodology meant to support engineering design activities for complex systems design. Nuclear fusion devices design complexity derives from contextual presence of both a challenging operating domain requiring frontier technology and a restrictive regulation on safety or systems compatibility aspects. System engineering methodologies adapted to nuclear design environment reduce risks of late design changes related to compatibility problems emerging at integration stage. Present work describes the methodology developed for the conceptual design phase of a nuclear fusion neutronic diagnostic, the Radial Neutron Camera for ITER plant. In particular the focus is on the characterization of design intents and the structured exploration of design domain aiming at baseline architecture to be engineered in next design phase. A formal definition of design domain space in terms of architectural elements has been developed to allow the instantiation of a set of candidate options. The instantiation process was structured according to sub-system intrinsic information content and potential mutual impact. Finally, architectural options have been assessed according to a specifically defined ranking function able to integrate information characterizing the candidate architectures deriving from different domains enabling a close collaboration with stakeholders. © 2018 Elsevier B.V.

The neutron efficiency of a Gas Electron Multiplier (GEM)-based detector designed for fast neutron measurements in fusion devices was determined through the combined use of Monte Carlo (MCNPX) calculations and analysis of deuterium–deuterium and deuterium–tritium neutron irradiation experiments. The detector, characterized by a triple GEM structure flushed with a Ar/CO 2 /CF 4 – 45/15/40 gas mixture, features a digital read-out system and has two sub-units for the detection of 2.5+14 MeV neutrons and 14 MeV neutrons ( U DD and U DT , respectively). The pulse height spectra (PHS) determined from the curves of experimental efficiency as a function of the detector's high voltage (HV) and the MCNPX-simulated PHS were compared using a fitting routine that finds the best match between the experimental and simulated PHS by assuming a parametric model for the relation between HV (that determines the detector's gain) and the energy deposited in the gas. This led to express the experimental neutron efficiency as a function of the discrimination level set on the deposited energy ( energy threshold ). The detector sensitivity to γ-rays was also analyzed and the operational range in which the γ-ray contribution to the signal is not negligible was determined. It is found that this detector can reach a maximum neutron efficiency of ~1×10 −3 counts/n at 2.5 MeV ( U DD sub-unit) and of ~4×10 −3 counts/n at 14 MeV ( U DT and U DD sub-units).

The Radial Neutron Camera (RNC), located in the ITER Equatorial Port Plug 1 (EPP1), is designed to provide the neutron emissivity profile through the measurement of the neutron flux along several collimated channels. The present design of the RNC is based on collimating structures: an ex-port system viewing the plasma core and an in-port system composed by two detector cassettes viewing the upper and lower plasma edges. A design of the EPP1 in which the diagnostics are installed in three completely independent vertical drawers is under study. In this frame, space optimization and integration issues suggest two possible solutions for the layout of the in-port RNC cassettes: the first one in which both cassettes are located in a side drawer; the second one in which the two cassettes lie in the central drawer, on opposite sides of the ex-port RNC cut-out. This paper describes the work performed to assess the impact of the two different in-port system layouts on the capability of the RNC to measure the neutron emissivity profile by means of MCNP and diagnostic performance calculations. The results of the analysis provide guidelines for the integration of the RNC into the EPP1 showing that the proximity of the in-port cassettes to the ex-port cut-out strongly increases the amount of uncollimated and scattered neutrons at the detector positions, thus reducing the diagnostic measurement capability. © 2013 Euratom-ENEA Association sulla Fusione.

The JET neutron profile monitor provides the measurement of the neutron flux along 19 collimated lines of sight from which the neutron emissivity profile can be obtained through reconstruction based on inversion methods. The neutron detectors are liquid organic scintillators featuring n/γ pulse shape discrimination. A recent digital upgrade of the neutron profile monitor acquisition system (200 MSamples/s sampling rate per channel, 14 bit resolution) offers new real-time capabilities. An algorithm performing real-time n/γ discrimination by means of the charge comparison method is implemented in the acquisition system FPGA. The algorithm produces two distinct count rates (n and γ) that are sent to the JET real time network ready for control applications and are simultaneously stored into the JET archive together with all the samples of each pulse. The paper describes the architecture of the FPGA implementation and reports the analysis of data collected during the 2011-2012 JET campaigns. The comparison between the real-time and post-processed (off-line) neutron count rates shows an agreement within 5% for all 19 detectors. Moreover, it is shown that the maximum count rate sustainable by the acquisition system when storing raw data (∼900 kHz as evaluated in laboratory tests) can be extended up to 5 MHz when using the real-time implementation with no local data storage. Finally, a statistical analysis of the ratio between the line-integrated measurements from the neutron profile monitor and the neutron rate from the JET neutron monitors is presented. © 2013 Elsevier B.V. All rights reserved.

tThe Radial Neutron Camera (RNC) and the Radial Gamma-Ray Spectrometer (RGRS) are two ITER diag-nostics, devoted, respectively, to the Real-Time (RT) measurement of the neutron emissivity profile andto the measurement of the confined alpha profile and runaway electrons. The two systems are closelyrelated as they share the same equatorial port plug and part of the lines-of-sight and both require theacquisition of event-based signals from radiation detectors.The RNC Data Acquisition and Processing (DAQP) system should be capable of handling peak countrates of the order of 106counts per second for a time duration up to 500 s. Moreover, for a continuousdata throughput, the DAQP system of both diagnostics shall provide two separate DMA channels, capableto transfer simultaneously event-based data and RT processed data from the digitizers to the host. ADAQP prototype will be developed to identify and study critical issues.The present paper will: i) present the RNC DAQP prototype showing its compliancy with the RNC plantsystem Fast Controller; ii) show the scalability of the actual RNC DAQP from the prototype concept; iii)identify the differences between the RNC and RGRS DAQP needs; iv) describe the RGRS DAQP system andits interface to the ITER Control Data Access and Communication.© 2017 Elsevier B.V. All rights reserved

The commonly adopted scaling for the maximum achievable plasma density in tokamak fusion devices, the so-called 'Greenwald limit', refers to the line-averaged density along a central chord and depends only on the average plasma current density. However, the Greenwald limit has been exceeded in tokamak experiments in the case of peaked density profiles, indicating that the edge density is the real parameter responsible for the density limit. Furthermore, the Greenwald limit has been obtained for fixed density profiles, so that the scaling can be very different when introducing density profile dependencies on plasma parameters. Dedicated density limit experiments were performed in recent years on the Frascati Tokamak Upgrade, exploring the high density domain in a wide range of values of plasma current, toroidal magnetic field and edge safety factor. New data were collected in the latest experimental campaigns, extending the study of the density limit towards lower values of toroidal magnetic field and plasma current. These experiments confirmed the edge nature of the density limit, as a Greenwald-like scaling was obtained for the maximum achievable line-averaged density along a peripheral chord, while a clear scaling of the maximum achievable line-averaged density along a central chord with the toroidal magnetic field only was found and successfully interpreted as due to interplay between the peripheral Greenwald limit and the specific density profile behavior when approaching the density limit. In particular, an analytical relation between the peripheral and the central density limit was derived for the first time, with the introduction of a generalized parabolic density profile with the peaking factor dependent on the plasma parameters. © 2017 IOP Publishing Ltd.

Special issue featuring the invited talks from the 43rd EPS Conference on Plasma Physics, Leuven, 4-8 July, 2016 We present an overview of FTU experiments on runaway electron (RE) generation and control carried out through a comprehensive set of real-time (RT) diagnostics/control systems and newly installed RE diagnostics. An RE imaging spectrometer system detects visible and infrared synchrotron radiation. A Cherenkov probe measures RE escaping the plasma. A gamma camera provides hard x-ray radial profiles from RE bremsstrahlung interactions in the plasma. Experiments on the onset and suppression of RE show that the threshold electric field for RE generation is larger than that expected according to a purely collisional theory, but consistent with an increase due to synchrotron radiation losses. This might imply a lower density to be targeted with massive gas injection for RE suppression in ITER. Experiments on active control of disruption-generated RE have been performed through feedback on poloidal coils by implementing an RT boundary-reconstruction algorithm evaluated on magnetic moments. This work was carried out within the framework of the EUROfusion Consortium and received funding from the Euratom research and training programme 2014–2018 under grant agreement No 633053 (Projects MST2-9 and MST2-15). The views and opinions expressed herein do not necessarily reflect those of the European Commission. Additional financial support was received from MINECO (Spain), Projects No. ENE2012-31753 and ENE2015-66444-R. Publicado

The 2014–2016 JET results are reviewed in the light of their significance for optimising the ITER research plan for the active and non-active operation. More than 60 h of plasma operation with ITER first wall materials successfully took place since its installation in 2011. New multi-machine scaling of the type I-ELM divertor energy flux density to ITER is supported by first principle modelling. ITER relevant disruption experiments and first principle modelling are reported with a set of three disruption mitigation valves mimicking the ITER setup. Insights of the L–H power threshold in Deuterium and Hydrogen are given, stressing the importance of the magnetic configurations and the recent measurements of fine-scale structures in the edge radial electric. Dimensionless scans of the core and pedestal confinement provide new information to elucidate the importance of the first wall material on the fusion performance. H-mode plasmas at ITER triangularity (H = 1 at ßN ~ 1.8 and n/nGW ~ 0.6) have been sustained at 2 MA during 5 s. The ITER neutronics codes have been validated on high performance experiments. Prospects for the coming D–T campaign and 14 MeV neutron calibration strategy are reviewed. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 under grant agreement No 633053. Peer Reviewed Article signat per 1.173 autors/es: X. Litaudon35, S. Abduallev39, M. Abhangi46, P. Abreu53, M. Afzal7, K.M. Aggarwal29, T. Ahlgren101, J.H. Ahn8, L. Aho-Mantila112, N. Aiba69, M. Airila112, R. Albanese105, V. Aldred7, D. Alegre93, E. Alessi45, P. Aleynikov55, A. Alfier12, A. Alkseev72, M. Allinson7, B. Alper7, E. Alves53, G. Ambrosino105, R. Ambrosino106, L. Amicucci90, V. Amosov88, E. Andersson Sundén22, M. Angelone90, M. Anghel85, C. Angioni62, L. Appel7, C. Appelbee7, P. Arena30, M. Ariola106, H. Arnichand8, S. Arshad41, A. Ash7, N. Ashikawa68, V. Aslanyan64, O. Asunta1, F. Auriemma12, Y. Austin7, L. Avotina103, M.D. Axton7, C. Ayres7, M. Bacharis24, A. Baciero57, D. Baião53, S. Bailey7, A. Baker7, I. Balboa7, M. Balden62, N. Balshaw7, R. Bament7, J.W. Banks7, Y.F. Baranov7, M.A. Barnard7, D. Barnes7, M. Barnes27, R. Barnsley55, A. Baron Wiechec7, L. Barrera Orte34, M. Baruzzo12, V. Basiuk8, M. Bassan55, R. Bastow7, A. Batista53, P. Batistoni90, R. Baughan7, B. Bauvir55, L. Baylor73, B. Bazylev56, J. Beal110, P.S. Beaumont7, M. Beckers39, B. Beckett7, A. Becoulet8, N. Bekris35, M. Beldishevski7, K. Bell7, F. Belli90, M. Bellinger7, É. Belonohy62, N. Ben Ayed7, N.A. Benterman7, H. Bergsåker42, J. Bernardo53, M. Bernert62, M. Berry7, L. Bertalot55, C. Besliu7, M. Beurskens63, B. Bieg61, J. Bielecki47, T. Biewer73, M. Bigi12, P. Bílková50, F. Binda22, A. Bisoffi31, J.P.S. Bizarro53, C. Björkas101, J. Blackburn7, K. Blackman7, T.R. Blackman7, P. Blanchard33, P. Blatchford7, V. Bobkov62, A. Boboc7, G. Bodnár113, O. Bogar18, I. Bolshakova60, T. Bolzonella12, N. Bonanomi97, F. Bonelli56, J. Boom62, J. Booth7, D. Borba35,53, D. Borodin39, I. Borodkina39, A. Botrugno90, C. Bottereau8, P. Boulting7, C. Bourdelle8, M. Bowden7, C. Bower7, C. Bowman110, T. Boyce7, C. Boyd7, H.J. Boyer7, J.M.A. Bradshaw7, V. Braic87, R. Bravanec40, B. Breizman107, S. Bremond8, P.D. Brennan7, S. Breton8, A. Brett7, S. Brezinsek39, M.D.J. Bright7, M. Brix7, W. Broeckx78, M. Brombin12, A. Brosławski65, D.P.D. Brown7, M. Brown7, E. Bruno55, J. Bucalossi8, J. Buch46, J. Buchanan7, M.A. Buckley7, R. Budny76, H. Bufferand8, M. Bulman7, N. Bulmer7, P. Bunting7, P. Buratti90, A. Burckhart62, A. Buscarino30, A. Busse7, N.K. Butler7, I. Bykov42, J. Byrne7, P. Cahyna50, G. Calabrò90, I. Calvo57, Y. Camenen4, P. Camp7, D.C. Campling7, J. Cane7, B. Cannas17, A.J. Capel7, P.J. Card7, A. Cardinali90, P. Carman7, M. Carr7, D. Carralero62, L. Carraro12, B.B. Carvalho53, I. Carvalho53, P. Carvalho53, F.J. Casson7, C. Castaldo90, N. Catarino53, J. Caumont7, F. Causa90, R. Cavazzana12, K. Cave-Ayland7, M. Cavinato12, M. Cecconello22, S. Ceccuzzi90, E. Cecil76, A. Cenedese12, R. Cesario90, C.D. Challis7, M. Chandler7, D. Chandra46, C.S. Chang76, A. Chankin62, I.T. Chapman7, S.C. Chapman28, M. Chernyshova49, G. Chitarin12, G. Ciraolo8, D. Ciric7, J. Citrin38, F. Clairet8, E. Clark7, M. Clark7, R. Clarkson7, D. Clatworthy7, C. Clements7, M. Cleverly7, J.P. Coad7, P.A. Coates7, A. Cobalt7, V. Coccorese105, V. Cocilovo90, S. Coda33, R. Coelho53, J.W. Coenen39, I. Coffey29, L. Colas8, S. Collins7, D. Conka103, S. Conroy22, N. Conway7, D. Coombs7, D. Cooper7, S.R. Cooper7, C. Corradino30, Y. Corre8, G. Corrigan7, S. Cortes53, D. Coster62, A.S. Couchman7, M.P. Cox7, T. Craciunescu86, S. Cramp7, R. Craven7, F. Crisanti90, G. Croci97, D. Croft7, K. Crombé15, R. Crowe7, N. Cruz53, G. Cseh113, A. Cufar81, A. Cullen7, M. Curuia85, A. Czarnecka49, H. Dabirikhah7, P. Dalgliesh7, S. Dalley7, J. Dankowski47, D. Darrow76, O. Davies7, W. Davis55,76, C. Day56, I.E. Day7, M. De Bock55, A. de Castro57, E. de la Cal57, E. de la Luna57, G. De Masi12, J. L. de Pablos57, G. De Temmerman55, G. De Tommasi105, P. de Vries55, K. Deakin7, J. Deane7, F. Degli Agostini12, R. Dejarnac50, E. Delabie73, N. den Harder38, R.O. Dendy7, J. Denis8, P. Denner39, S. Devaux62,104, P. Devynck8, F. Di Maio55, A. Di Siena62, C. Di Troia90, P. Dinca86, R. D’Inca62, B. Ding51, T. Dittmar39, H. Doerk62, R.P. Doerner9, T. Donné34, S.E. Dorling7, S. Dormido-Canto93, S. Doswon7, D. Douai8, P.T. Doyle7, A. Drenik62,81, P. Drewelow63, P. Drews39, Ph. Duckworth55, R. Dumont8, P. Dumortier58, D. Dunai113, M. Dunne62, I. Ďuran50, F. Durodié58, P. Dutta46, B. P. Duval33, R. Dux62, K. Dylst78, N. Dzysiuk22, P.V. Edappala46, J. Edmond7, A.M. Edwards7, J. Edwards7, Th. Eich62, A. Ekedahl8, R. El-Jorf7, C.G. Elsmore7, M. Enachescu84, G. Ericsson22, F. Eriksson16, J. Eriksson22, L.G. Eriksson36, B. Esposito90, S. Esquembri94, H.G. Esser39, D. Esteve8, B. Evans7, G.E. Evans7, G. Evison7, G.D. Ewart7, D. Fagan7, M. Faitsch62, D. Falie86, A. Fanni17, A. Fasoli33, J. M. Faustin33, N. Fawlk7, L. Fazendeiro53, N. Fedorczak8, R.C. Felton7, K. Fenton7, A. Fernades53, H. Fernandes53, J. Ferreira53, J.A. Fessey7, O. Février8, O. Ficker50, A. Field7, S. Fietz62, A. Figueiredo53, J. Figueiredo53,35, A. Fil8, P. Finburg7, M. Firdaouss8, U. Fischer56, L. Fittill7, M. Fitzgerald7, D. Flammini90, J. Flanagan7, C. Fleming7, K. Flinders7, N. Fonnesu90, J. M. Fontdecaba57, A. Formisano79, L. Forsythe7, L. Fortuna30, E. Fortuna-Zalesna19, M. Fortune7, S. Foster7, T. Franke34, T. Franklin7, M. Frasca30, L. Frassinetti42, M. Freisinger39, R. Fresa98, D. Frigione90, V. Fuchs50, D. Fuller35, S. Futatani6, J. Fyvie7, K. Gál34,62, D. Galassi2, K. Gałązka49, J. Galdon-Quiroga92, J. Gallagher7, D. Gallart6, R. Galvão10, X. Gao51, Y. Gao39, J. Garcia8, A. Garcia-Carrasco42, M. García-Muñoz92, J.-L. Gardarein3, L. Garzotti7, P. Gaudio95, E. Gauthier8, D.F. Gear7, S.J. Gee7, B. Geiger62, M. Gelfusa95, S. Gerasimov7, G. Gervasini45, M. Gethins7, Z. Ghani7, M. Ghate46, M. Gherendi86, J.C. Giacalone8, L. Giacomelli45, C.S. Gibson7, T. Giegerich56, C. Gil8, L. Gil53, S. Gilligan7, D. Gin54, E. Giovannozzi90, J.B. Girardo8, C. Giroud7, G. Giruzzi8, S. Glöggler62, J. Godwin7, J. Goff7, P. Gohil43, V. Goloborod’ko102, R. Gomes53, B. Gonçalves53, M. Goniche8, M. Goodliffe7, A. Goodyear7, G. Gorini97, M. Gosk65, R. Goulding76, A. Goussarov78, R. Gowland7, B. Graham7, M.E. Graham7, J. P. Graves33, N. Grazier7, P. Grazier7, N.R. Green7, H. Greuner62, B. Grierson76, F.S. Griph7, C. Grisolia8, D. Grist7, M. Groth1, R. Grove73, C.N. Grundy7, J. Grzonka19, D. Guard7, C. Guérard34, C. Guillemaut8,53, R. Guirlet8, C. Gurl7, H.H. Utoh69, L.J. Hackett7, S. Hacquin8,35, A. Hagar7, R. Hager76, A. Hakola112, M. Halitovs103, S.J. Hall7, S.P. Hallworth Cook7, C. Hamlyn-Harris7, K. Hammond7, C. Harrington7, J. Harrison7, D. Harting7, F. Hasenbeck39, Y. Hatano108, D.R. Hatch107, T.D.V. Haupt7, J. Hawes7, N.C. Hawkes7, J. Hawkins7, P. Hawkins7, P.W. Haydon7, N. Hayter7, S. Hazel7, P.J.L. Heesterman7, K. Heinola101, C. Hellesen22, T. Hellsten42, W. Helou8, O.N. Hemming7, T.C. Hender7, M. Henderson55, S.S. Henderson21, R. Henriques53, D. Hepple7, G. Hermon7, P. Hertout8, C. Hidalgo57, E.G. Highcock27, M. Hill7, J. Hillairet8, J. Hillesheim7, D. Hillis73, K. Hizanidis70, A. Hjalmarsson22, J. Hobirk62, E. Hodille8, C.H.A. Hogben7, G.M.D. Hogeweij38, A. Hollingsworth7, S. Hollis7, D.A. Homfray7, J. Horáček50, G. Hornung15, A.R. Horton7, L.D. Horton36, L. Horvath110, S.P. Hotchin7, M.R. Hough7, P.J. Howarth7, A. Hubbard64, A. Huber39, V. Huber39, T.M. Huddleston7, M. Hughes7, G.T.A. Huijsmans55, C.L. Hunter7, P. Huynh8, A.M. Hynes7, D. Iglesias7, N. Imazawa69, F. Imbeaux8, M. Imríšek50, M. Incelli109, P. Innocente12, M. Irishkin8, I. Ivanova-Stanik49, S. Jachmich58,35, A.S. Jacobsen83, P. Jacquet7, J. Jansons103, A. Jardin8, A. Järvinen1, F. Jaulmes38, S. Jednoróg49, I. Jenkins7, C. Jeong20, I. Jepu86, E. Joffrin8, R. Johnson7, T. Johnson42, Jane Johnston7, L. Joita7, G. Jones7, T.T.C. Jones7, K.K. Hoshino69, A. Kallenbach62, K. Kamiya69, J. Kaniewski7, A. Kantor7, A. Kappatou62, J. Karhunen1, D. Karkinsky7, I. Karnowska7, M. Kaufman73, G. Kaveney7, Y. Kazakov58, V. Kazantzidis70, D.L. Keeling7, T. Keenan7, J. Keep7, M. Kempenaars7, C. Kennedy7, D. Kenny7, J. Kent7, O.N. Kent7, E. Khilkevich54, H.T. Kim35, H.S. Kim80, A. Kinch7, C. king7, D. King7, R.F. King7, D.J. Kinna7, V. Kiptily7, A. Kirk7, K. Kirov7, A. Kirschner39, G. Kizane103, C. Klepper73, A. Klix56, P. Knight7, S.J. Knipe7, S. Knott96, T. Kobuchi69, F. Köchl111, G. Kocsis113, I. Kodeli81, L. Kogan7, D. Kogut8, S. Koivuranta112, Y. Kominis70, M. Köppen39, B. Kos81, T. Koskela1, H.R. Koslowski39, M. Koubiti4, M. Kovari7, E. Kowalska-Strzęciwilk49, A. Krasilnikov88, V. Krasilnikov88, N. Krawczyk49, M. Kresina8, K. Krieger62, A. Krivska58, U. Kruezi7, I. Książek48, A. Kukushkin72, A. Kundu46, T. Kurki-Suonio1, S. Kwak20, R. Kwiatkowski65, O.J. Kwon13, L. Laguardia45, A. Lahtinen101, A. Laing7, N. Lam7, H.T. Lambertz39, C. Lane7, P.T. Lang62, S. Lanthaler33, J. Lapins103, A. Lasa101, J.R. Last7, E. Łaszyńska49, R. Lawless7, A. Lawson7, K.D. Lawson7, A. Lazaros70, E. Lazzaro45, J. Leddy110, S. Lee66, X. Lefebvre7, H.J. Leggate32, J. Lehmann7, M. Lehnen55, D. Leichtle41, P. Leichuer7, F. Leipold55,83, I. Lengar81, M. Lennholm36, E. Lerche58, A. Lescinskis103, S. Lesnoj7, E. Letellier7, M. Leyland110, W. Leysen78, L. Li39, Y. Liang39, J. Likonen112, J. Linke39, Ch. Linsmeier39, B. Lipschultz110, G. Liu55, Y. Liu51, V.P. Lo Schiavo105, T. Loarer8, A. Loarte55, R.C. Lobel7, B. Lomanowski1, P.J. Lomas7, J. Lönnroth1,35, J. M. López94, J. López-Razola57, R. Lorenzini12, U. Losada57, J.J. Lovell7, A.B. Loving7, C. Lowry36, T. Luce43, R.M.A. Lucock7, A. Lukin74, C. Luna5, M. Lungaroni95, C.P. Lungu86, M. Lungu86, A. Lunniss110, I. Lupelli7, A. Lyssoivan58, N. Macdonald7, P. Macheta7, K. Maczewa7, B. Magesh46, P. Maget8, C. Maggi7, H. Maier62, J. Mailloux7, T. Makkonen1, R. Makwana46, A. Malaquias53, A. Malizia95, P. Manas4, A. Manning7, M.E. Manso53, P. Mantica45, M. Mantsinen6, A. Manzanares91, Ph. Maquet55, Y. Marandet4, N. Marcenko88, C. Marchetto45, O. Marchuk39, M. Marinelli95, M. Marinucci90, T. Markovič50, D. Marocco90, L. Marot26, C.A. Marren7, R. Marshal7, A. Martin7, Y. Martin33, A. Martín de Aguilera57, F.J. Martínez93, J. R. Martín-Solís14, Y. Martynova39, S. Maruyama55, A. Masiello12, M. Maslov7, S. Matejcik18, M. Mattei79, G.F. Matthews7, F. Maviglia11, M. Mayer62, M.L. Mayoral34, T. May-Smith7, D. Mazon8, C. Mazzotta90, R. McAdams7, P.J. McCarthy96, K.G. McClements7, O. McCormack12, P.A. McCullen7, D. McDonald34, S. McIntosh7, R. McKean7, J. McKehon7, R.C. Meadows7, A. Meakins7, F. Medina57, M. Medland7, S. Medley7, S. Meigh7, A.G. Meigs7, G. Meisl62, S. Meitner73, L. Meneses53, S. Menmuir7,42, K. Mergia71, I.R. Merrigan7, Ph. Mertens39, S. Meshchaninov88, A. Messiaen58, H. Meyer7, S. Mianowski65, R. Michling55, D. Middleton-Gear7, J. Miettunen1, F. Militello7, E. Militello-Asp7, G. Miloshevsky77, F. Mink62, S. Minucci105, Y. Miyoshi69, J. Mlynář50, D. Molina8, I. Monakhov7, M. Moneti109, R. Mooney7, S. Moradi37, S. Mordijck43, L. Moreira7, R. Moreno57, F. Moro90, A.W. Morris7, J. Morris7, L. Moser26, S. Mosher73, D. Moulton7,1, A. Murari12,35, A. Muraro45, S. Murphy7, N.N. Asakura69, Y.S. Na80, F. Nabais53, R. Naish7, T. Nakano69, E. Nardon8, V. Naulin83, M.F.F. Nave53, I. Nedzelski53, G. Nemtsev88, F. Nespoli33, A. Neto41, R. Neu62, V.S. Neverov72, M. Newman7, K.J. Nicholls7, T. Nicolas33, A.H. Nielsen83, P. Nielsen12, E. Nilsson8, D. Nishijima99, C. Noble7, M. Nocente97, D. Nodwell7, K. Nordlund101, H. Nordman16, R. Nouailletas8, I. Nunes53, M. Oberkofler62, T. Odupitan7, M.T. Ogawa69, T. O’Gorman7, M. Okabayashi76, R. Olney7, O. Omolayo7, M. O’Mullane21, J. Ongena58, F. Orsitto11, J. Orszagh18, B.I. Oswuigwe7, R. Otin7, A. Owen7, R. Paccagnella12, N. Pace7, D. Pacella90, L.W. Packer7, A. Page7, E. Pajuste103, S. Palazzo30, S. Pamela7, S. Panja46, P. Papp18, R. Paprok50, V. Parail7, M. Park66, F. Parra Diaz27, M. Parsons73, R. Pasqualotto12, A. Patel7, S. Pathak46, D. Paton7, H. Patten33, A. Pau17, E. Pawelec48, C. Paz Soldan43, A. Peackoc36, I.J. Pearson7, S.-P. Pehkonen112, E. Peluso95, C. Penot55, A. Pereira57, R. Pereira53, P.P. Pereira Puglia7, C. Perez von Thun35,39, S. Peruzzo12, S. Peschanyi56, M. Peterka50, P. Petersson42, G. Petravich113, A. Petre84, N. Petrella7, V. Petržilka50, Y. Peysson8, D. Pfefferlé33, V. Philipps39, M. Pillon90, G. Pintsuk39, P. Piovesan12, A. Pires dos Reis52, L. Piron7, A. Pironti105, F. Pisano17, R. Pitts55, F. Pizzo79, V. Plyusnin53, N. Pomaro12, O.G. Pompilian86, P.J. Pool7, S. Popovichev7, M.T. Porfiri90, C. Porosnicu86, M. Porton7, G. Possnert22, S. Potzel62, T. Powell7, J. Pozzi7, V. Prajapati46, R. Prakash46, G. Prestopino95, D. Price7, M. Price7, R. Price7, P. Prior7, R. Proudfoot7, G. Pucella90, P. Puglia52, M.E. Puiatti12, D. Pulley7, K. Purahoo7, Th. Pütterich62, E. Rachlew25, M. Rack39, R. Ragona58, M.S.J. Rainford7, A. Rakha6, G. Ramogida90, S. Ranjan46, C.J. Rapson62, J.J. Rasmussen83, K. Rathod46, G. Rattá57, S. Ratynskaia82, G. Ravera90, C. Rayner7, M. Rebai97, D. Reece7, A. Reed7, D. Réfy113, B. Regan7, J. Regaña34, M. Reich62, N. Reid7, F. Reimold39, M. Reinhart34, M. Reinke110,73, D. Reiser39, D. Rendell7, C. Reux8, S.D.A. Reyes Cortes53, S. Reynolds7, V. Riccardo7, N. Richardson7, K. Riddle7, D. Rigamonti97, F.G. Rimini7, J. Risner73, M. Riva90, C. Roach7, R.J. Robins7, S.A. Robinson7, T. Robinson7, D.W. Robson7, R. Roccella55, R. Rodionov88, P. Rodrigues53, J. Rodriguez7, V. Rohde62, F. Romanelli90, M. Romanelli7, S. Romanelli7, J. Romazanov39, S. Rowe7, M. Rubel42, G. Rubinacci105, G. Rubino12, L. Ruchko52, M. Ruiz94, C. Ruset86, J. Rzadkiewicz65, S. Saarelma7, R. Sabot8, E. Safi101, P. Sagar7, G. Saibene41, F. Saint-Laurent8, M. Salewski83, A. Salmi112, R. Salmon7, F. Salzedas53, D. Samaddar7, U. Samm39, D. Sandiford7, P. Santa46, M.I.K. Santala1, B. Santos53, A. Santucci90, F. Sartori41, R. Sartori41, O. Sauter33, R. Scannell7, T. Schlummer39, K. Schmid62, V. Schmidt12, S. Schmuck7, M. Schneider8, K. Schöpf102, D. Schwörer32, S.D. Scott76, G. Sergienko39, M. Sertoli62, A. Shabbir15, S.E. Sharapov7, A. Shaw7, R. Shaw7, H. Sheikh7, A. Shepherd7, A. Shevelev54, A. Shumack38, G. Sias17, M. Sibbald7, B. Sieglin62, S. Silburn7, A. Silva53, C. Silva53, P.A. Simmons7, J. Simpson7, J. Simpson-Hutchinson7, A. Sinha46, S.K. Sipilä1, A.C.C. Sips36, P. Sirén112, A. Sirinelli55, H. Sjöstrand22, M. Skiba22, R. Skilton7, K. Slabkowska49, B. Slade7, N. Smith7, P.G. Smith7, R. Smith7, T.J. Smith7, M. Smithies110, L. Snoj81, S. Soare85, E. R. Solano35,57, A. Somers32, C. Sommariva8, P. Sonato12, A. Sopplesa12, J. Sousa53, C. Sozzi45, S. Spagnolo12, T. Spelzini7, F. Spineanu86, G. Stables7, I. Stamatelatos71, M.F. Stamp7, P. Staniec7, G. Stankūnas59, C. Stan-Sion84, M.J. Stead7, E. Stefanikova42, I. Stepanov58, A.V. Stephen7, M. Stephen46, A. Stevens7, B.D. Stevens7, J. Strachan76, P. Strand16, H.R. Strauss44, P. Ström42, G. Stubbs7, W. Studholme7, F. Subba75, H.P. Summers21, J. Svensson63, Ł. Świderski65, T. Szabolics113, M. Szawlowski49, G. Szepesi7, T.T. Suzuki69, B. Tál113, T. Tala112, A.R. Talbot7, S. Talebzadeh95, C. Taliercio12, P. Tamain8, C. Tame7, W. Tang76, M. Tardocchi45, L. Taroni12, D. Taylor7, K.A. Taylor7, D. Tegnered16, G. Telesca15, N. Teplova54, D. Terranova12, D. Testa33, E. Tholerus42, J. Thomas7, J.D. Thomas7, P. Thomas55, A. Thompson7, C.-A. Thompson7, V.K. Thompson7, L. Thorne7, A. Thornton7, A.S. Thrysøe83, P.A. Tigwell7, N. Tipton7, I. Tiseanu86, H. Tojo69, M. Tokitani67, P. Tolias82, M. Tomeš50, P. Tonner7, M. Towndrow7, P. Trimble7, M. Tripsky58, M. Tsalas38, P. Tsavalas71, D. Tskhakaya jun102, I. Turner7, M.M. Turner32, M. Turnyanskiy34, G. Tvalashvili7, S.G.J. Tyrrell7, A. Uccello45, Z. Ul-Abidin7, J. Uljanovs1, D. Ulyatt7, H. Urano69, I. Uytdenhouwen78, A.P. Vadgama7, D. Valcarcel7, M. Valentinuzzi8, M. Valisa12, P. Vallejos Olivares42, M. Valovic7, M. Van De Mortel7, D. Van Eester58, W. Van Renterghem78, G.J. van Rooij38, J. Varje1, S. Varoutis56, S. Vartanian8, K. Vasava46, T. Vasilopoulou71, J. Vega57, G. Verdoolaege58, R. Verhoeven7, C. Verona95, G. Verona Rinati95, E. Veshchev55, N. Vianello45, J. Vicente53, E. Viezzer62,92, S. Villari90, F. Villone100, P. Vincenzi12, I. Vinyar74, B. Viola90, A. Vitins103, Z. Vizvary7, M. Vlad86, I. Voitsekhovitch34, P. Vondráček50, N. Vora7, T. Vu8, W.W. Pires de Sa52, B. Wakeling7, C.W.F. Waldon7, N. Walkden7, M. Walker7, R. Walker7, M. Walsh55, E. Wang39, N. Wang39, S. Warder7, R.J. Warren7, J. Waterhouse7, N.W. Watkins28, C. Watts55, T. Wauters58, A. Weckmann42, J. Weiland23, H. Weisen33, M. Weiszflog22, C. Wellstood7, A.T. West7, M.R. Wheatley7, S. Whetham7, A.M. Whitehead7, B.D. Whitehead7, A.M. Widdowson7, S. Wiesen39, J. Wilkinson7, J. Williams7, M. Williams7, A.R. Wilson7, D.J. Wilson7, H.R. Wilson110, J. Wilson7, M. Wischmeier62, G. Withenshaw7, A. Withycombe7, D.M. Witts7, D. Wood7, R. Wood7, C. Woodley7, S. Wray7, J. Wright7, J.C. Wright64, J. Wu89, S. Wukitch64, A. Wynn110, T. Xu7, D. Yadikin16, W. Yanling39, L. Yao89, V. Yavorskij102, M.G. Yoo80, C. Young7, D. Young7, I.D. Young7, R. Young7, J. Zacks7, R. Zagorski49, F.S. Zaitsev18, R. Zanino75, A. Zarins103, K.D. Zastrow7, M. Zerbini90, W. Zhang62, Y. Zhou42, E. Zilli12, V. Zoita86, S. Zoletnik113, I. Zychor65 and JET Contributorsa // EUROfusion Consortium JET, Culham Science Centre, Abingdon, OX14 3DB, United Kingdom / 1 Aalto University, PO Box 14100, FIN-00076 Aalto, Finland / 2 Aix Marseille Université, CNRS, Centrale Marseille, M2P2 UMR 7340, 13451, Marseille, France / 3 Aix-Marseille Université, CNRS, IUSTI UMR 7343, 13013 Marseille, France / 4 Aix-Marseille Université, CNRS, PIIM, UMR 7345, 13013 Marseille, France / 5 Arizona State University, Tempe, AZ, United States of America / 6 Barcelona Supercomputing Center, Barcelona, Spain / 7 CCFE, Culham Science Centre, Abingdon, Oxon, OX14 3DB, United Kingdom / 8 CEA, IRFM, F-13108 Saint Paul Lez Durance, France / 9 Center for Energy Research, University of California at San Diego, La Jolla, CA 92093, United States of America / 10 Centro Brasileiro de Pesquisas Fisicas, Rua Xavier Sigaud, 160, Rio de Janeiro CEP 22290-180, Brazil / 11 Consorzio CREATE, Via Claudio 21, 80125 Napoli, Italy / 12 Consorzio RFX, corso Stati Uniti 4, 35127 Padova, Italy / 13 Daegu University, Jillyang, Gyeongsan, Gyeongbuk 712-174, Republic of Korea / 14 Departamento de Física, Universidad Carlos III de Madrid, 28911 Leganés, Madrid, Spain / 15 Department of Applied Physics UG (Ghent University) St-Pietersnieuwstraat 41 B-9000 Ghent, Belgium / 16 Department of Earth and Space Sciences, Chalmers University of Technology, SE-41296 Gothenburg, Sweden / 17 Department of Electrical and Electronic Engineering, University of Cagliari, Piazza d’Armi 09123, Cagliari, Italy / 18 Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics Comenius University Mlynska dolina F2, 84248 Bratislava, Slovakia / 19 Department of Materials Science, Warsaw University of Technology, PL-01-152 Warsaw, Poland / 20 Department of Nuclear and Quantum Engineering, KAIST, Daejeon 34141, Korea / 21 Department of Physics and Applied Physics, University of Strathclyde, Glasgow, G4 ONG, United Kingdom / 22 Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala, Sweden / 23 Department of Physics, Chalmers University of Technology, SE-41296 Gothenburg, Sweden / 24 Department of Physics, Imperial College London, London, SW7 2AZ, United Kingdom / 25 Department of Physics, SCI, KTH, SE-10691 Stockholm, Sweden / 26 Department of Physics, University of Basel, Basel, Switzerland / 27 Department of Physics, University of Oxford, Oxford, OX1 2JD, United Kingdom / 28 Department of Physics, University of Warwick, Coventry, CV4 7AL, United Kingdom / 29 Department of Pure and Applied Physics, Queens University, Belfast, BT7 1NN, United Kingdom / 30 Dipartimento di Ingegneria Elettrica Elettronica e Informatica, Università degli Studi di Catania, 95125 Catania, Italy / 31 Dipartimento di Ingegneria Industriale, University of Trento, Trento, Italy / 32 Dublin City University (DCU), Dublin, Ireland / 33 Ecole Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland / 34 EUROfusion Programme Management Unit, Boltzmannstr. 2, 85748 Garching, Germany / 35 EUROfusion Programme Management Unit, Culham Science Centre, Culham, OX14 3DB, United Kingdom / 36 European Commission, B-1049 Brussels, Belgium / 37 Fluid and Plasma Dynamics, ULB—Campus Plaine—CP 231 Boulevard du Triomphe, 1050 Bruxelles, Belgium / 38 FOM Institute DIFFER, Eindhoven, Netherlands / 39 Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung—Plasmaphysik, 52425 Jülich, Germany / 40 Fourth State Research, 503 Lockhart Dr, Austin, TX, United States of America / 41 Fusion for Energy Joint Undertaking, Josep Pl. 2, Torres Diagonal Litoral B3, 08019, Barcelona, Spain / 42 Fusion Plasma Physics, EES, KTH, SE-10044 Stockholm, Sweden / 43 General Atomics, PO Box 85608, San Diego, CA 92186-5608, United States of America / 44 HRS Fusion, West Orange, NJ, United States of America / 45 IFP-CNR, via R. Cozzi 53, 20125 Milano, Italy / 46 Institute for Plasma Research, Bhat, Gandhinagar-382 428, Gujarat State, India / 47 Institute of Nuclear Physics, Radzikowskiego 152, 31-342 Kraków, Poland / 48 Institute of Physics, Opole University, Oleska 48, 45-052 Opole, Poland / 49 Institute of Plasma Physics and Laser Microfusion, Hery 23, 01-497 Warsaw, Poland / 50 Institute of Plasma Physics AS CR, Za Slovankou 1782/3, 182 00 Praha 8, Czechia / 51 Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, People’s Republic of China / 52 Instituto de Física, Universidade de São Paulo, Rua do Matão Travessa R Nr.187 CEP 05508-090 Cidade Universitária, São Paulo, Brasil / 53 Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal / 54 Ioffe Physico-Technical Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russian Federation / 55 ITER Organization, Route de Vinon, CS 90 046, 13067 Saint Paul Lez Durance, France / 56 Karlsruhe Institute of Technology, PO Box 3640, D-76021 Karlsruhe, Germany / 57 Laboratorio Nacional de Fusión, CIEMAT, Madrid, Spain / 58 Laboratory for Plasma Physics Koninklijke Militaire School—Ecole Royale Militaire, Renaissancelaan 30 Avenue de la Renaissance B-1000, Brussels, Belgium / 59 Lithuanian energy institute, Breslaujos g. 3, LT-44403, Kaunas, Lithuania / 60 Magnetic Sensor Laboratory, Lviv Polytechnic National University, Lviv, Ukraine / 61 Maritime University of Szczecin, Waly Chrobrego 1-2, 70-500 Szczecin, Poland / 62 Max-Planck-Institut für Plasmaphysik, D-85748 Garching, Germany / 63 Max-Planck-Institut für Plasmaphysik, Teilinsitut Greifswald, D-17491 Greifswald, Germany / 64 MIT Plasma Science and Fusion Centre, Cambridge, MA 02139, United States of America / 65 National Centre for Nuclear Research (NCBJ), 05-400 Otwock-Świerk, Poland / 66 National Fusion Research Institute (NFRI), 169-148 Gwahak-ro, Yuseong-gu, Daejeon 305-806, Republic of Korea / 67 National Institute for Fusion Science, Oroshi, Toki, Gifu 509-5292, Japan / 68 National Institute for Fusion Science, Toki, 509-5292, Japan / 69 National Institutes for Quantum and Radiological Science and Technology, Naka, Ibaraki 311-0193, Japan / 70 National Technical University of Athens, Iroon Politechniou 9, 157 73 Zografou, Athens, Greece / 71 NCSR ‘Demokritos’, 153 10, Agia Paraskevi Attikis, Greece / 72 NRC Kurchatov Institute, 1 Kurchatov Square, Moscow 123182, Russian Federation / 73 Oak Ridge National Laboratory, Oak Ridge, TN 37831-6169, United States of America / 74 PELIN LLC, 27a, Gzhatskaya Ulitsa, Saint Petersburg, 195220, Russian Federation / 75 Politecnico di Torino, Corso Duca degli Abruzzi 24, I-10129 Torino, Italy / 76 Princeton Plasma Physics Laboratory, James Forrestal Campus, Princeton, NJ 08543, United States of America / 77 Purdue University, 610 Purdue Mall, West Lafayette, IN 47907, United States of America / 78 SCK-CEN, Nuclear Research Centre, 2400 Mol, Belgium / 79 Second University of Napoli, Consorzio CREATE, Via Claudio 21, 80125 Napoli, Italy / 80 Seoul National University, Shilim-Dong, Gwanak-Gu, Republic of Korea / 81 Slovenian Fusion Association (SFA), Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia / 82 Space and Plasma Physics, EES, KTH SE-100 44 Stockholm, Sweden / 83 Technical University of Denmark, Department of Physics, Bldg 309, DK-2800 Kgs Lyngby, Denmark / 84 The ‘Horia Hulubei’ National Institute for Physics and Nuclear Engineering, Magurele-Bucharest, Romania / 85 The National Institute for Cryogenics and Isotopic Technology, Ramnicu Valcea, Romania / 86 The National Institute for Laser, Plasma and Radiation Physics, Magurele-Bucharest, Romania / 87 The National Institute for Optoelectronics, Magurele-Bucharest, Romania / 88 Troitsk Insitute of Innovating and Thermonuclear Research (TRINITI), Troitsk 142190, Moscow Region, Russian Federation / 89 University of Electronic Science and Technology of China, Chengdu, People’s Republic of China / 90 Unità Tecnica Fusione, ENEA C. R. Frascati, via E. Fermi 45, 00044 Frascati (Roma), Italy / 91 Universidad Complutense de Madrid, Madrid, Spain / 92 Universidad de Sevilla, Sevilla, Spain / 93 Universidad Nacional de Educación a Distancia, Madrid, Spain / 94 Universidad Politécnica de Madrid, Grupo I2A2, Madrid, Spain / 95 Università di Roma Tor Vergata, Via del Politecnico 1, Roma, Italy / 96 University College Cork (UCC), Ireland / 97 University Milano-Bicocca, piazza della Scienza 3, 20126 Milano, Italy / 98 University of Basilicata, Consorzio CREATE, Via Claudio 21, 80125 Napoli, Italy / 99 University of California, 1111 Franklin St., Oakland, CA 94607, United States of America / 100 University of Cassino, Consorzio CREATE, Via Claudio 21, 80125 Napoli, Italy / 101 University of Helsinki, PO Box 43, FI-00014 University of Helsinki, Finland / 102 University of Innsbruck, Fusion@Österreichische Akademie der Wissenschaften (ÖAW), Innsbruck, Austria / 103 University of Latvia, 19 Raina Blvd., Riga, LV 1586, Latvia / 104 University of Lorraine, CNRS, UMR7198, YIJL, Nancy, France / 105 University of Napoli ‘Federico II’, Consorzio CREATE, Via Claudio 21, 80125 Napoli, Italy / 106 University of Napoli Parthenope, Consorzio CREATE, Via Claudio 21, 80125 Napoli, Italy / 107 University of Texas at Austin, Institute for Fusion Studies, Austin, TX 78712, United States of America / 108 University of Toyama, Toyama, 930-8555, Japan / 109 University of Tuscia, DEIM, Via del Paradiso 47, 01100 Viterbo, Italy / 110 University of York, Heslington, York YO10 5DD, United Kingdom / 111 Vienna University of Technology, Fusion@Österreichische Akademie der Wissenschaften (ÖAW), Austria / 112 VTT Technical Research Centre of Finland, PO Box 1000, FIN-02044 VTT, Finland / 113 Wigner Research Centre for Physics, PO Box 49, H-1525 Budapest, Hungary

The Radial Neutron Camera (RNC) of ITER is a collimated multichannel neutron detection system intended to characterize fusion plasma neutron source. The RNC diagnostic plays a primary role in the ITER Program for advanced control measurements and physics studies. It also acts as backup system by providing machine protection and basic control measurements. The aim of ITER is to prove the viability of fusion as an energy source and to collect the data necessary for the design and subsequent operation of the first electricity-producing fusion power plant. The expected ITER pulse duration is up to 500 s in the inductive scenario. The demanding ITER operating conditions require a real-time Data AcQuisition and Processing (DAQP) system that will acquire analog signals from the RNC detectors (e.g. scintillators, CVD diamonds, fission chambers) providing digital data throu2gh high performance networks to the ITER database. Two DAQP systems are expected to be used as prototypes for preliminary tests of performance: one based on PCI Express Extensions for Instrumentation (PXIe) and another one based on Advanced Telecommunications Computing Architecture (ATCA). The ATCA based system, with an architecture capable of withstanding a sustainable throughput of the order of 0.5 GB/s of data per channel, will be presented. The system features high performance Field Programmable Gate Arrays (FPGA) for every two 12 bits channels, sampling up to 1.6 GSPS and high performance host computers for every 4 channels through ×16 PCIe 2.0 links. The criteria used for the choice of the components of both systems, ATCA and PXIe take into account: i) data throughput; ii) realtime data reduction; iii) compression, and iv) pulse processing. Finally, the expected data throughput performance of both architectures will be discussed.

A Compact Neutron Spectrometer (CNS) has been developed to measure the neutron emission spectra in Joint European Torus (JET) fusion plasma experiments. The spectrometer, based on a liquid scintillation detector (BC501A), is equipped with a Digital Pulse Shape Discrimination (DPSD) acquisition system for neutron (n) and gamma-ray (γ) separation. The CNS enables recording the n and γ pulse height spectra (PHS) up to total count rates of ~106 s-1. Energy resolution, after PHS unfolding, will be

The ITER Equatorial Port 1 will host the following diagnostic systems: the Radial Neutron Camera (RNC), the High Resolution Neutron Spectrometer (HRNS), the Gamma Ray Spectrometer, the Hard X-Rays Monitor, the Pressure Gauges, the Bolometers, the Equatorial Visible/Infrared Wide Angle Viewing System (WAVS), the Neutron Flux Monitor (NFM), the Motional Stark Effect (MSE) system and the Divertor Impurity Monitor (DIM). These diagnostics are integrated inside the Port Plug, a water-cooled stainless steel support structure, which also includes Diagnostic Shielding Modules, designed to provide enough radiation shielding capabilities, to protect the diagnostic systems and to reduce the dose level in the Port Interspace. A new concept for the design of the Port Plug is under consideration: it is based on the installation of the diagnostics inside vertical drawers, completely independent from each other, that are inserted in the Port Plug structure through guiding rails. The paper presents the results of three-dimensional neutronic analyses performed with MCNP5 Monte Carlo code in support of the Port Plug design and integration. The reference ITER MCNP 40° model “Alite” has been updated including the details of the drawers and three diagnostics. Nuclear heating radial profiles have been produced for different toroidal and poloidal positions to be used as input for thermal and thermo-mechanical analyses. 3-D Neutron flux maps have been calculated in order to assess the effect of radiation streaming through all gaps (between the drawers, around the Port Plug and along the diagnostic penetrations) and to provide an estimate of the shielding effectiveness of the new Port Plug concept.

This paper presents the results of neutronic calculations performed to address important issues related to the optimization of the ITER HRNS (High resolution Neutron Spectrometer) design, in particular concerning the definition of the collimator and the choice of the detector system. The calculations have been carried out using the MCNP5 Monte Carlo code in a full 3-D geometry. The HRNS collimation system has been included in the latest MCNP ITER 40 model (Alite-4). The ITER scenario 2 reference DT plasma fusion neutron source peaked at 14.1 MeV with Gaussian energy distribution has been used. Neutron fluxes and energy spectra (>1 MeV) have been evaluated at different positions along the HRNS collimator and at the detector location. The noise-to-signal ratio (i.e. the ratio of collided to uncoilided neutrons), the breakdown of the collided spectrum into its components, the dependency on the first wall aperture and the gamma-ray spectra at the detector position have also been analyzed. The impact of the results on the design of the HRNS diagnostic system is discussed.

The 2D neutron emissivity profile is measured at JET by a set of NE213 liquid organic scintillators, located in two fan-shaped arrays of collimators with 10 horizontal and 9 vertical lines of sight. As the detectors are sensitive to neutron and gamma rays, pulse shape analysis is required for neutron/gamma discrimination. A digital architecture data-handling data acquisition and processing for the entire diagnostic has been developed by ENEA-Frascati and installed at JET during the 2009 campaign as a replacement of the existing analogue electronics. This paper describes the performances of the digital system and the first experimental results in the JET C27b campaign.

Advanced C++ programming methods as well as fast Pulse Detection Algorithms (PDA) have been implemented in order to increase the computing speed of a LabVIEW™ data processing software developed for a Digital Pulse Shape Discrimination (DPSD) system for liquid scintillators. The newly implemented PDAs are described and compared: the most efficient method has been implemented in the data processing software, which has also been ported into C++. The comparison of the computing speeds of the new and old versions of the PDAs are presented. Program summary Program title: DPDS – Digital Pulse Detection Software Catalogue identifier: AEHQ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHQ_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 454 070 No. of bytes in distributed program, including test data, etc.: 20 987 104 Distribution format: tar.gz Programming language: C++ (Borland Visual C++) Computer: IBM PC Operating system: MS Windows 2000 and later… RAM

A new neutron flux monitor for fusion applications (DT _GEM) has been developed by means of a triple-GEM (Gas Electron Multiplier), a proton recoil converter and a low energy proton absorber. The design and the optimization for the detection of 14 MeV neutrons have been performed using MCNPX and FLUKA Monte Carlo Codes and the detector has been tested under 14 MeV neutron irradiation at the Frascati Neutron Generator (FNG). Polyethylene is used as a converter and an aluminum absorber sheet covers a triple 10 times 10 cm2 GEM filled with an Ar/CO2/CF4 gas mixture. The detector is read out with 64 pads (10 times 6 mm2) in a 4 times 16 matrix. The DT_ GEM design and the results of the first tests performed at FNG are presented and discussed in this paper. Excellent performances at high count rates in transient neutron flux, good efficiency, low sensitivity to gamma radiation and high voltage stability under irradiation make the DT_GEM a promising detector for neutron diagnostics in fusion.

The exploitation of ITER tokamak will require diagnostics for machine protection, inputs to plasma control systems, evaluation and analysis of plasma parameters and performances. The equatorial visible/infrared wide angle viewing system and the radial neutron camera are the two main diagnostics of Procurement Package 11 (PP11), one of the diagnostic procurements under the responsibility of Europe, which also contains Equatorial Port Plug 1 and seven other diagnostics supplied by Europe or other ITER partners and integrated in the same Port Plug. Significant progress has recently been made in the development of the equatorial visible/infrared wide angle viewing system and the radial neutron camera. This paper gives an overview of the major technical achievements on these two diagnostics and points out the urgent needed R&D activities.

Liquid scintillation detectors are widely used in nuclear/high-energy physics and nuclear fusion for spectral measurements in mixed radiation fields due to their compactness, fast response and neutron/gamma discrimination capabilities. The use of response functions evaluated for the specific system and of appropriate methods of data analysis allows such systems to be used as broadband spectrometers for photons and neutrons. System stability and ability to reach high throughput count rates are key challenges for several applications (e.g., neutron spectrometry for nuclear fusion devices), but standard analog electronics limits the operation of liquid scintillation neutron spectrometers to low count rates ( ~ 3 ldr 104 s-1) . The count rate capabilities of a liquid scintillation neutron spectrometer (NE213 detector) from the Physikalisch-Technische Bundesanstalt (PTB) has been extended up to ~ 4.2 ldr 105 s-1, by coupling it to a digital acquisition system developed at ENEA-Frascati. Measurements have been carried out at PTB using gamma sources and accelerator-produced 2.5 MeV and 14 MeV neutrons. For 14 MeV neutron measurements, digital pulse height spectra (PHS) obtained at high count rates have been compared to PHS recorded with standard analog electronics. The results show that stable PHS (within 1%) can be obtained at high count rate despite the high sensitivity of the gain of photomultiplier tubes to count rate variations.

The radial neutron camera (RNC) will provide the spatial distribution and the total strength of the ITER neutron source (emissivity profile and fusion power) by means of collimated neutron measurements. Line-integrated neutron spectral measurements can also provide information on the ion temperature profile. The present design of the RNC consists of two collimating structures for a full coverage of the plasma: 36 collimated lines of sight (LOS) distributed in three different planes view the plasma core (ex-port system) and nine collimated LOS view the plasma edge (in-port system). The RNC design is based on the combined use of the MCNP Monte Carlo code and a software tool performing asymmetric Abel inversion of simulated measured neutron signals (MSST). Neutron and γ-ray transport calculations are performed with MCNP using a 3D RNC model to determine the signal/noise for each RNC channel and the spectra at the detectors. The MSST code is used to check the RNC compliance with the ITER measurement requirements for the neutron emissivity profile. In the present paper the improvement of the hard variance reduction technique applied to the MCNP neutron source (consisting in sampling neutrons only from plasma regions contributing to the detector signal) is presented and the following issues are analyzed: the possibility of reducing the length of the ex-port collimators (resulting in a significant reduction of the overall RNC dimension and weight); options for the reduction of the dose due to the neutron streaming through the RNC cut-outs in the blanket shielding module; the integration of a γ-ray detection system in the RNC by partially filling the collimators with a neutron absorbing material (LiH).

Pile-up events in radiation detectors are those in which two or more pulses partly or completely overlap. In standard analog electronics pile-up events are rejected using a pile-up inspector. When digital acquisition techniques are used, the recorded waveforms of pile-ups can be elaborated and the contributing single pulses reconstructed. A method for the off-line digital processing of pile-ups from liquid organic scintillators (NE213) is proposed: pile-ups in which the overlapping pulses are separated more than 15 ns can be reduced to single pulses and then correctly identified as neutrons (n) or gammas (γ). An analysis of the errors introduced by the method is carried out. The method has been applied to data acquired in the mixed n–γ field of JET deuterium plasma discharges from the NE213 detector in the central line of sight of the neutron profile monitor and the results are described.

Experiments have been carried out to evaluate the threshold electric field for runaway generation during the flat-top phase of ohmic discharges in the Frascati Tokamak Upgrade tokamak. An investigation of the conditions for runaway electron generation and suppression has been performed for a wide range of plasma parameter values. The measured threshold electric field is found to be significantly larger (similar to 2 - 5 times) than predicted by the relativistic collissional theory of runaway generation, E-R = n(e) e(3) ln Lambda/4 pi e(0)(2) m(e) c(2), and can be explained to a great extent by an increase of the critical electric field due to the effect of the electron synchrotron radiation losses. These findings are consistent with the results of an ITPA joint experiment to study the onset, growth, and decay of relativistic runaway electrons [Granetz et al., Phys. Plasmas 21, 072506 (2014)]. Confirmation of these results for disruptions with high electric field might imply significantly lower requirements on electron densities for suppression and prevention of runaway formation in ITER. This work was carried out with financial support from Dirección General de Investigación, Científica y Técnica, Project No. ENE2012-31753 (MINECO; Spain). Publicado

In the perspective of reducing ITER risks, JET next DT campaign presents a unique potential, since the device can combine the right first wall material mix, the reactor fuel mixture and sufficient dimensions and fields to confine the alpha particles. An integrated diagnostic programme, to maximize the scientific output of this DT campaign, is under way and concentrates mainly on the diagnostic for the fusion products, on advanced measurements for instabilities and on testing diagnostic technologies in a 14 MeV neutron environment.

This paper summarizes the work, performed in the frame of various EFDA contracts during 2004–2005, on the design review and upgrade of the ITER radial neutron camera (RNC). The RNC, which should provide information on the spatial distribution and energy spectrum of the neutron emission, consists of an ex-vessel system (fan-like collimator with 12 × 3 lines of sights) and an in-vessel system with further 9 lines for a full coverage of the plasma. A Monte Carlo code (MCNP) has been used for the neutronic calculations. The basic ITER model has been developed from the CATIA drawings to include the RNC with all details relevant for the neutronic analysis. In the model the collimator diameters have been set to 2 and 4 cm, respectively, for the ex-vessel and in-vessel systems. A detailed space dependent fusion neutron source (DD and DT phases in various plasma scenarios) has been used with a consistent ion temperature radial profile. A special variance reduction treatment has been developed so that neutrons reach the far regions in the high collimated neutron beam and score with a satisfying statistical error. Neutron and photon fluxes and spectra have been calculated. Approximately, one neutron out of 1011 emitted in all the plasma reaches a single ex-vessel detector. Therefore, for an emission rate of 1.8 × 1020 n/s (corresponding to 500 MW fusion power) the flux on the detectors is in the range (1–5) × 108 n/(cm2 s) depending on the poloidal orientation. The fraction of scattered neutrons (>1 MeV) is lower than few % of the total. A measurement simulation software tool (MSST) performing asymmetric Abel inversion of simulated measured neutron signals has also been developed for line of sight and design optimization. Combining information from MCNP calculations and MSST, it has been possible to evaluate the performance of the RNC, check whether the present design of the RNC meets the measurement requirements and optimize the RNC design.