M. Nocente
A5002290299- Magnetic confinement fusion research
- Nuclear Physics and Applications
- Fusion materials and technologies
- Ionosphere and magnetosphere dynamics
- Radiation Detection and Scintillator Technologies
- Particle accelerators and beam dynamics
- Nuclear reactor physics and engineering
- Superconducting Materials and Applications
- Atomic and Subatomic Physics Research
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Solar and Space Plasma Dynamics
- Particle Detector Development and Performance
- Radioactive contamination and transfer
- Nuclear physics research studies
- Laser-induced spectroscopy and plasma
- Diamond and Carbon-based Materials Research
- Advanced Data Storage Technologies
- Radioactivity and Radon Measurements
- High-pressure geophysics and materials
- Atomic and Molecular Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Radioactive element chemistry and processing
- Astro and Planetary Science
- High-Energy Particle Collisions Research
University of Milano-Bicocca
2016-2025
National Agency for New Technologies, Energy and Sustainable Economic Development
1990-2024
Institute for the Science and Technology of Plasmas
2019-2024
National Research Council
2015-2024
National Academies of Sciences, Engineering, and Medicine
2024
Max Planck Institute for Plasma Physics
2016-2024
University of Padua
2024
University of Milan
2010-2021
Peking University
2019-2021
National Centre for Nuclear Research
2021
Abstract In JET deuterium-tritium (D-T) plasmas, the fusion power is produced through thermonuclear reactions and between thermal ions fast particles generated by neutral beam injection (NBI) heating or accelerated electromagnetic wave in ion cyclotron range of frequencies (ICRFs). To complement experiments with 50/50 D/T mixtures maximizing reactivity, a scenario dominant non-thermal reactivity has been developed successfully demonstrated during second campaign DTE2, as it was predicted to...
Recent experiments on the Type I ELMy H-mode regime performed at JET with improved diagnostics have expanded range of parameters for study ELM energy and particle losses. Deviations from standard behaviour such losses in some areas operating space revealed that are correlated (density temperature) pedestal plasma before crash, while other global characteristics (such as frequency) a consequence ELM-driven flux in-between confinement. The relative loss (to energy) is found to correlate well...
High resolution neutron emission spectroscopy (NES) and gamma-ray (GRS) measurements of fast ions in high power fusion plasmas are reviewed. NES is a well established diagnostics the velocity distribution fuel was recently used to investigate interaction energetic with MHD instabilities. energy GRS on more recent application shown provide information function minority accelerated by ICRH, such as 4He 3He. Starting from today's D plasmas, ion DT burning plasma next step tokamaks, ITER,...
Abstract Ion cyclotron resonance frequency (ICRF) heating has been an essential component in the development of high power H-mode scenarios Jet European Torus ITER-like wall (JET-ILW). The ICRF performance was improved by enhancing antenna-plasma coupling with dedicated main chamber gas injection, including preliminary minimization RF-induced plasma-wall interactions, while RF where optimized for core impurity screening terms ion position and minority hydrogen concentration. impact on...
First simultaneous measurements of deuterium-deuterium (DD) and deuterium-tritium neutrons from deuterium plasmas using a Single crystal Diamond Detector are presented in this paper. The were performed at JET with dedicated electronic chain that combined high count rate capabilities energy resolution. deposited spectrum DD was successfully reproduced by means Monte Carlo calculations the detector response function simulations neutron emission plasma, including background contributions....
On the road to a fusion reactor, thorough control of fast-ion distribution plays crucial role. Fusion-born $$\alpha$$ -particles are, indeed, necessary ingredient self-sustained burning plasmas. Recent developments in diagnostic distributions have significantly improved our predictive capabilities towards future devices. Here, we review key techniques for confined and lost fast ions tokamak stellarator We discuss neutron gamma-ray spectroscopy, D- collective Thomson scattering, neutral...
This paper summarizes the physical principles behind novel three-ion scenarios using radio frequency waves in ion cyclotron range of frequencies (ICRF). We discuss how to transform mode conversion electron heating into a new flexible ICRF technique for and fast-ion generation multi-ion species plasmas. The theoretical section provides practical recipes selecting plasma composition realize scenarios, including two equivalent possibilities choice resonant absorbers that have been identified....
Abstract In the paper we present an overview of interpretive modelling a database JET-ILW 2021 D-T discharges using TRANSP code. The main aim is to assess our capability computationally reproducing fusion performance various plasma scenarios different external heating and mixtures, understand driving mechanisms. We find that simulations confirm general power-law relationship between increasing power output, which supported by absolutely calibrated neutron yield measurements. A comparison...
At present, magnetic confinement fusion devices rely solely on absolute neutron counting as a direct way of measuring power. Absolute deuterium-tritium gamma rays could provide the secondary neutron-independent technique required for validation scientific results and licensing tool future power plants. However, this approach necessitates an accurate determination gamma-ray-to-neutron branching ratio. The ratio reaction ^{3}H(^{2}H,γ)^{5}He/^{3}H(^{2}H,n)^{4}He was determined in plasmas at...
The spectral 𝛾 ray emission from the reaction 3H(2H,𝛾)5He has been measured for first time in a magnetic confinement deuterium-tritium plasma experiment at Joint European Torus. A custom developed gamma spectrometer system based on LaBr3 scintillator combined to LiH neutron attenuator and zero dead fast digital data acquisition allowed measure weak under ≈105 more intense 14MeV field. 𝑅-matrix analysis of 5He nucleus used predict expected spectrum which compared with measurement, but...
Neutron measurement is the primary tool in SPARC tokamak for fusion power (Pfus) monitoring, research on physics of burning plasmas, validation neutronics simulation workflows, and providing feedback machine protection. A demanding target uncertainty (10% Pfus) coverage a wide dynamic range (>8 orders magnitude going up to 5 × 1019 n/s), coupled with fast-track timeline design deployment, make development neutron diagnostics challenging. Four subsystems are under that exploit high...
Phase-space time-resolved measurements of fast-ion losses induced by edge localized modes (ELMs) and ELM mitigation coils have been obtained in the ASDEX Upgrade tokamak means multiple loss detectors (FILDs). Filament-like bursts are measured during ELMs several FILDs at different toroidal poloidal positions. Externally applied magnetic perturbations (MPs) little effect on plasma profiles, including fast-ions, high collisionality plasmas with mitigated ELMs. A strong impact density, rotation...
A new high efficiency, resolution, fast γ-ray spectrometer was recently installed at the JET tokamak. The is based on a LaBr3(Ce) scintillator coupled to photomultiplier tube. digital data acquisition system used allow spectrometry with event rates in excess of 1 MHz expected future DT plasmas. However, lower typical present day experiments, digitization can degrade energy resolution system, depending algorithms for extracting pulse height information from digitized pulses. In this paper,...
High resolution γ-ray spectroscopy measurements at MHz counting rates were carried out nuclear accelerators, combining a LaBr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> (Ce) detector with dedicated hardware and software solutions based on digitization off-line analysis. Spectra measured up to 4 MHz, little or no degradation of the energy resolution, adopting pile rejection algorithm. The reported results represent step forward...
The spectral broadening of characteristic γ-ray emission peaks from the reaction (12)C((3)He,pγ)(14)N was measured in D((3)He) plasmas JET tokamak with ion cyclotron resonance heating tuned to fundamental harmonic (3)He. Intensities and detailed shapes were successfully reproduced using a physics model combining kinetics reacting ions description nuclear differential cross sections for populating L1-L8 (14)N excitation levels yielding observed emission. results provide paradigm, which...
Observations made in a JET experiment aimed at accelerating deuterons to the MeV range by third harmonic radiofrequency (RF) heating coupled into deuterium beam are reported.Measurements based on set of advanced neutron and gamma-ray spectrometers that, for first time, observe plasma simultaneously along vertical oblique lines sight.Parameters fast ion energy distribution, such as high cut-off deuteron distribution function RF coupling constant, determined from data within uniform analysis...
We demonstrate the measurement of a 2D MeV-range ion velocity distribution function by velocity-space tomography at JET. Deuterium ions were accelerated into third harmonic cyclotron resonance heating. made measurements with three neutron emission spectrometers and high-resolution γ-ray spectrometer detecting γ-rays released in two reactions. The tomographic inversion based on these five spectra is excellent agreement numerical simulations ASCOT–RFOF SPOT–RFOF codes. length measured fast-ion...
The fast-ion distribution from third harmonic ion cyclotron resonance frequency (ICRF) heating on the Joint European Torus is studied using neutron emission spectroscopy with time-of-flight spectrometer TOFOR. energy dependence of fast deuteron function inferred measured spectrum neutrons born in DD fusion reactions, and compared theoretical models for ICRF heating. Good agreements between modelling measurements are seen clear features function, that due to finite Larmor radius resonating...
Abstract High-resolution γ -ray spectroscopy (GRS) measurements resolve spectral shapes of Doppler-broadened -rays. We calculate weight functions describing velocity-space sensitivities any two-step reaction GRS in magnetized plasmas using the resonant nuclear 9 Be( α , n ) 12 C as an example. The energy-dependent cross sections this suggest that is sensitive to alpha particles above about 1.7 MeV and highly at resonance energies reaction. Here we demonstrate high-resolution are not only...
Single crystal Diamond Detectors (SDD) are being increasingly exploited for neutron diagnostics in high power fusion devices, given their significant radiation hardness and energy resolution capabilities. The geometrical efficiency of SDDs is limited by the size commercially available crystals, which often smaller than dimension beams along collimated lines sight tokamak devices. In this work, we present design fabrication a 14 MeV spectrometer consisting 12 diamond pixels arranged matrix,...
We here present the principles and main physics capabilities behind design of radial gamma ray spectrometers (RGRS) system for alpha particle runaway electron measurements at ITER. The diagnostic benefits from recent advances in gamma-ray spectrometry tokamak plasmas combines space high energy resolution a single device. RGRS as designed can provide information on particles time scale 1/10 slowing down ITER 500 MW full power DT scenario. Spectral observations 3.21 4.44 MeV peaks reaction...
Dedicated experiments to generate energetic D ions and fusion-born alpha particles were performed at the Joint European Torus (JET) with ITER-like wall (ILW). Using 3-ion radio frequency (RF) heating scenario, deuterium from neutral beam injection (NBI) accelerated in core of mixed plasmas higher energies ion cyclotron resonance (ICRF) waves, turn leading a core-localized source particles. The fast-ion distribution RF-accelerated D-NBI was controlled by varying ICRF NBI power ( 4–6 MW, 3–20...