P. Buratti
A5041788679- Magnetic confinement fusion research
- Fusion materials and technologies
- Ionosphere and magnetosphere dynamics
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Laser-Plasma Interactions and Diagnostics
- Solar and Space Plasma Dynamics
- Nuclear reactor physics and engineering
- Gyrotron and Vacuum Electronics Research
- Nuclear Physics and Applications
- Dust and Plasma Wave Phenomena
- Atomic and Subatomic Physics Research
- Laser-induced spectroscopy and plasma
- Geomagnetism and Paleomagnetism Studies
- Physics of Superconductivity and Magnetism
- Radiation Detection and Scintillator Technologies
- Quantum, superfluid, helium dynamics
- High-Energy Particle Collisions Research
- High-pressure geophysics and materials
- Electrostatic Discharge in Electronics
- Advanced Fiber Optic Sensors
- Vibration and Dynamic Analysis
- Magnetic Bearings and Levitation Dynamics
- Photonic and Optical Devices
National Agency for New Technologies, Energy and Sustainable Economic Development
2016-2025
University of Rome Tor Vergata
2022-2023
National Institute for Astrophysics
2021-2023
Gran Sasso Science Institute
2023
Agenzia Spaziale Italiana
2023
Accademia Nazionale dei Lincei
2023
National Centre for Nuclear Research
2021
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
1979-2020
Royal Military Academy
2020
Institute of Ionized Gas
2019
A survey has been carried out into the causes of all 2309 disruptions over last decade JET operations. The aim this was to obtain a complete picture possible disruption causes, in order devise better strategies prevent or mitigate their impact. analysis allows effort avoid be more efficient and effective. As expected, highly complex pattern chain events that led emerged. It found majority had technical root cause, for example due control errors, operator mistakes. These bring random,...
The replacement of the JET carbon wall (C-wall) by a Be/W ITER-like (ILW) has affected plasma energy confinement. To investigate this, experiments have been performed with both C-wall and ILW to vary heating power over wide range for plasmas different shapes.
Abstract An overview is presented of the progress since 2021 in construction and scientific programme preparation Divertor Tokamak Test (DTT) facility. Licensing for building has been granted at end 2021. Cat. A radiologic source also 2022. The toroidal field magnet system progressing. prototype 170 GHz gyrotron produced it now under test on FALCON design vacuum vessel, poloidal coils civil infrastructures completed. shape first DTT divertor agreed with EUROfusion to different plasma exhaust...
We discuss the processes underlying excitation of fishbone-like internal kink instabilities driven by supra-thermal electrons generated experimentally different means: electron cyclotron resonance heating (ECRH) and lower hybrid (LH) power injection. The peculiarity interest exciting these fishbones ECRH only or LH is also analysed. Not mode stability explained, but transition between steady state nonlinear oscillations to bursting (almost regular) pulsations, as observed in FTU, interpreted...
The scan of ion cyclotron resonant heating (ICRH) power has been used to systematically study the pump out effect central electron on impurities such as Ni and Mo in H-mode low collisionality discharges JET. transport parameters have measured by introducing a transient perturbation their densities via laser blow off technique. Without ICRH density profiles are typically peaked. application induces plasma centre (at normalized poloidal flux ρ = 0.2) an outward drift approximately proportional...
A new technique has been developed to produce plasmas with improved confinement relative the H98,y2 scaling law (ITER Physics Expert Groups on Confinement and Transport Modelling Database ITER Basics Editors EDA 1999 Nucl. Fusion 39 2175) JET tokamak. In mid-size tokamaks ASDEX upgrade DIII-D heating during current formation is used a flat q-profile minimum close 1. On this leads q-profiles similar q but opposite other not an state. By changing method utilizing faster ramp temporary higher...
In the recent JET experimental campaigns with new ITER-like wall (JET-ILW), major progress has been achieved in characterization and operation of H-mode regime metallic environments: (i) plasma breakdown at first attempt X-point L-mode recovered a few days operation; (ii) stationary stable type-I ELMy H-modes βN ∼ 1.4 have low high triangularity shape plasmas are showing that their operational domain H = 1 is significantly reduced JET-ILW mainly because need to inject large amount gas (above...
Type I ELMy H-mode operation in JET with the ITER-like Be/W wall (JET-ILW) generally occurs at lower pedestal pressures compared to those full carbon (JET-C). The density is similar but temperature where type ELMs occur reduced and below so-called critical I–type III transition reported JET-C experiments. Furthermore, confinement factor H98(y,2) baseline plasmas JET-ILW low power fractions Ploss/Pthr,08 < 2 (where Ploss (Pin − dW/dt), Pthr,08 L–H threshold from Martin et al 2008 (J. Phys....
Abstract In this work the onset of tearing modes in termination phase plasma pulses on JET is investigated. It shown that broadening or shrinking current density profile, as a consequence core hollowing an edge cooling electron temperature strongly increases probability destabilizing 2/1 mode also absence external trigger (e.g. sawtooth crash). Two parameters are defined to highlight changes shape profile can lead MHD instabilities and empirical stability diagram introduced into space two...
In 2003, the performance of 'hybrid' regime was successfully validated in JET experiments up to βN = 2.8 at low toroidal field (1.7 T), with plasma triangularity and normalized Larmor radius (ρ*) corresponding identical ASDEX Upgrade discharges. Stationary conditions have been achieved fusion figure merit ( ) reaching 0.42 q95 3.9. The discharges show similar MHD, edge current profile behaviour, when compared Upgrade. addition, extended hybrid scenario operation higher 2.4 T lower ρ* towards...
The TCV tokamak is augmenting its unique historical capabilities (strong shaping, strong electron heating) with ion heating, additional heating compatible high densities, and variable divertor geometry, in a multifaceted upgrade program designed to broaden operational range without sacrificing fundamental flexibility. rooted three-pronged approach aimed at ITER support, explorations towards DEMO, research. A 1 MW, tangential neutral beam injector (NBI) was recently installed promptly...
Abstract The research program of the TCV tokamak ranges from conventional to advanced-tokamak scenarios and alternative divertor configurations, exploratory plasmas driven by theoretical insight, exploiting device’s unique shaping capabilities. Disruption avoidance real-time locked mode prevention or unlocking with electron-cyclotron resonance heating (ECRH) was thoroughly documented, using magnetic radiation triggers. Runaway generation high- Z noble-gas injection runaway dissipation...
The existence of fishbone fluctuations at frequencies comparable to those geodesic acoustic modes (GAM) and beta induced Alfvén eigenmodes (BAE) has been demonstrated theoretically in a recent work (Zonca et al 2007 Nucl. Fusion 47 1588 ). Here, we show that observation fishbones unexpectedly high JET (Nabais 2005 Phys. Plasmas 12 102509) is well interpreted as experimental evidence (GAM/BAE range) frequency discuss the insights concerning both supra-thermal particles thermal plasma...
We present an overview of FTU experiments on runaway electron (RE) generation and control carried out through a comprehensive set real-time (RT) diagnostics/control systems newly installed RE diagnostics. An imaging spectrometer system detects visible infrared synchrotron radiation. A Cherenkov probe measures escaping the plasma. gamma camera provides hard x-ray radial profiles from bremsstrahlung interactions in Experiments onset suppression show that threshold electric field for is larger...
Since the 2012 IAEA-FEC Conference, FTU operations have been largely devoted to runaway electrons generation and control, exploitation of 140 GHz electron cyclotron (EC) system liquid metal limiter elements. Experiments on shown that measured threshold electric field for their is larger than predicted by collisional theory can be justified considering synchrotron radiation losses. A new control algorithm was developed tested in presence a current plateau, allowing minimize interactions with...
In Hybrid plasma operation in JET with its ITER-like wall (JET-ILW) it is found that n>1 tearing activity can significantly enhance the rate of on-axis peaking tungsten impurities, which turn degrades discharge performance. Core n=1 instabilities be beneficial removing impurities from core (e.g. sawteeth or fishbones), but conversely also degrade confinement (particularly combination simultaneous n=3 activity). The nature MHD discharges, both previous Carbon and subsequent JET-ILW, surveyed...
Within the EUROfusion MST1 work package, a series of experiments has been conducted on AUG and TCV devices to disentangle role plasma fueling shape for onset small ELM regimes. On both devices, regimes with high confinement are achieved if only two conditions fulfilled at same time. Firstly, density separatrix must be large enough (), leading pressure profile flattening separatrix, which stabilizes type-I ELMs. Secondly, magnetic configuration close double null (DN), reduction shear in...
Integrating the plasma core performance with an edge and scrape-off layer (SOL) that leads to tolerable heat particle loads on wall is a major challenge. The new European medium size tokamak task force (EU-MST) coordinates research ASDEX Upgrade (AUG), MAST TCV. This multi-machine approach within EU-MST, covering wide parameter range, instrumental progress in field, as ITER DEMO core/pedestal SOL parameters are not achievable simultaneously present day devices. A two prong adopted. On one...
MHD spectroscopy in FTU has revealed high frequency (HF) oscillations between 30 and 70 kHz that accompany the development of large m0 = −2, n0 −1 islands ohmic plasmas. This range is one order magnitude above island rotation frequency, below first toroidal gap Alfvén continuum same low introduced by finite beta effects. The HF spectrum organized pairs modes with opposite numbers, n 1 for stronger ones, which form standing waves rest frame. poloidal structure |m| 2 main lines. lines appear...
With the exploration of MA plasma current regime in up to 0.5 s long discharges, RFX-mod has opened new and very promising perspectives for reversed field pinch (RFP) magnetic configuration, made significant progress understanding improving confinement controlling stability. A big leap with respect previous knowledge expectations on RFP physics performance been by since last 2006 IAEA Fusion Energy Conference. self-organized helical equilibrium experimentally achieved (the Single Helical...
Abstract The non-resonant magnetic braking effect induced by a non-axisymmetric perturbation is investigated on JET and TEXTOR. collisionality dependence of the torque n = 1, where toroidal mode number, generated error field correction coils observed. observed located mainly in plasma core (normalized radius ρ < 0.4) increases with decreasing collisionality. neoclassical viscosity (NTV) collisionless regime modelled using numerical solution bounce-averaged drift kinetic equation....
Abstract The confinement in JET baseline type I ELMy H-mode plasmas is compared to that so-called hybrid H-modes a database study of 112 with the carbon fibre composite (CFC) wall. typically have β N ∼ 1.5–2, H 98 1, whereas 2.5–3, < 1.5. contains both low- ( δ 0.2–0.25) and high-triangularity 0.4) from last operational campaigns CFC wall period 2008–2009. Based on detailed global as well pedestal core confinement, there no evidence form separate groups; it emerges transition between two...
Ion cyclotron resonance heating (ICRH) in the hydrogen minority scheme provides central ion and acts favorably on core tungsten transport. Full wave modeling shows that, at medium power level (4 MW), after collisional redistribution, ratio of transferred to ions electrons vary little with (hydrogen) concentration nH/ne but high-Z impurity screening provided by fast temperature increases concentration. The radiated JET discharges has been analyzed a large database covering 2013–2014 campaign....