A5038610332- Magnetic confinement fusion research
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Superconducting Materials and Applications
- Vacuum and Plasma Arcs
- Fusion materials and technologies
- Laser-Plasma Interactions and Diagnostics
- Electrostatic Discharge in Electronics
- Fluid Dynamics and Turbulent Flows
- Semiconductor materials and devices
- Particle Accelerators and Free-Electron Lasers
- Metal and Thin Film Mechanics
- Geomagnetism and Paleomagnetism Studies
- Advancements in Semiconductor Devices and Circuit Design
- Particle Detector Development and Performance
- High voltage insulation and dielectric phenomena
- NMR spectroscopy and applications
- Meteorological Phenomena and Simulations
- Nuclear Physics and Applications
- Heat Transfer Mechanisms
- Optical measurement and interference techniques
- Optical Coatings and Gratings
- Theoretical and Computational Physics
National Agency for New Technologies, Energy and Sustainable Economic Development
2012-2024
University of Padua
2015-2024
Institute for the Science and Technology of Plasmas
2022
Institute of Ionized Gas
1992-1995
Istituto Nazionale di Fisica Nucleare, Sezione di Padova
1993
The ITER Neutral Beam Test Facility (NBTF), called PRIMA (Padova Research on Megavolt Accelerator), is hosted in Padova, Italy and includes two experiments: MITICA, the full-scale prototype of heating neutral beam injector, SPIDER, full-size radio frequency negative-ions source. NBTF realization exploitation SPIDER MITICA have been recognized as necessary to make future operation injectors efficient reliable, fundamental achievement thermonuclear-relevant plasma parameters ITER. This paper...
Abstract The ITER Neutral Beam Test Facility (PRIMA) is presently under construction at Consorzio RFX (Padova, Italy). PRIMA includes two experimental devices: an ITER-size ion source with low voltage extraction, called SPIDER, and the full prototype of whole Heating Beams (HNBs), MITICA. purpose MITICA to demonstrate that all operational parameters HNB accelerator can be experimentally achieved, thus establishing a large step forward in performances neutral beam injectors comparison present...
Heating neutral beam (HNB) injectors, necessary to achieve burning conditions and control plasma instabilities in ITER, are characterized by such demanding parameters that a test facility (NBTF) dedicated their development optimization is being realized Padua (Italy) with direct contributions from the Italian government (through Consorzio RFX as host entity) ITER international organization (with kind domestic agencies of Europe, Japan India) technical scientific support various European...
The requirements of ITER neutral beam injectors (1 MeV, 40 A negative deuterium ion current for 1 h) have never been simultaneously attained; therefore, a dedicated Neutral Beam Test Facility (NBTF) was set up at Consorzio RFX (Padova, Italy). NBTF includes two experiments: SPIDER (Source the Production Ions Deuterium Extracted from Rf plasma), full-scale prototype source injectors, with 100 keV accelerator, to investigate and optimize properties source; MITICA, entire injector, devoted...
SPIDER is one of the two projects ITER Neutral Beam Test Facility (NBTF) under construction in Padova, Italy, at Consorzio RFX premises; it will have a 100 keV beam source with full-size prototype radiofrequency (RF) ion for Injector (NBI), designed to operate pulse length up 3600 s, featuring ITER-like filter field configuration, caesium oven layout and wide set diagnostics.These features allow reproducing operation like as cannot be done any other existing test facility.SPIDER realization...
Coherent structures identified in two reversed field pinch experiments are interpreted as a dynamic balance of dipolar and monopolar vortices growing evolving under the effect ExB flow shear. For first time their contribution to anomalous transport has been estimated fusion related plasmas, showing that they can account for up 50% total plasma diffusivity. The experimental findings indicate diffusion coefficient associated with coherent depends on relative population types is minimum when...
RFX-mod is a reversed field pinch (RFP) experiment equipped with system that actively controls the magnetic boundary. In this paper we describe results of new control algorithm, clean mode (CMC), in which aliasing sideband harmonics generated by discrete saddle coils corrected real time. CMC operation leads to smoother (i.e. more axisymmetric) Tearing modes rotate (up 100 Hz) and partially unlock. Plasma–wall interaction diminishes due decrease non-axisymmetric shift plasma column. With...
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...
A statistical analysis of the anomalous particle flux in edge region RFX experiment has revealed that laminar times between bursts, which account for more than 50% losses, have a power law distribution and fluctuations are not self-similar. These properties found contrast with wide class self-organized-criticality models so it is concluded there no experimental evidence avalanchelike process occurrence plasma RFX.
In order to test the self-organized criticality (SOC) paradigm in transport processes, a novel technique has been applied for first time plasmas confined reversed field pinch configuration. This consists of an analysis probability distribution function times between bursts density fluctuations measured by microwave reflectometry and electrostatic probes. The same also intermittent events sorted out from Gaussian background. both cases, experimental results disagree with predictions SOC system.
Optimization of machine operation, including plasma position control, density control and especially feedback on multiple magnetohydrodynamic modes, has led RFX-mod to operate reliably at 1.5 MA, the highest current ever achieved a reversed field pinch (RFP). At high low magnetic topology spontaneously self-organizes in an Ohmical helical symmetry, with new axis helically twisting around geometrical torus. The separatrix island disappears leaving wide symmetric thermal structure large...
The reversed field pinch configuration is characterized by the presence of magnetic structures both in core and at edge: core, high plasma current spontaneous development a helical structure accompanied appearance internal electron transport barriers; edge strong pressure gradients, identifying an barrier, are observed too, related to position reversal surface.
Turbulent structures detected in the edge plasma of fusion devices, often described as blobs, are generally believed to be responsible for confinement degradation. Recent experimental evidence and theories have suggested their filamentary electromagnetic nature. In this Letter first direct measurements parallel current density associated with turbulent a experiment reported. The nature is clearly shown by identifying filaments vortexlike velocity pattern pressure perturbation.
The modified RFX is a very flexible device used for variety of control schemes MHD instabilities and advanced reverse field pinch scenarios. Relative to the previous machine, RFX-mod has thin Cu shell with vertical penetration time τS, lowered from 450 50 ms shell/plasma proximity b/a = 1.24–1.1. Toroidal equilibrium feedback-controlled new power supplies provide better B control. Newly designed graphite tiles protect vessel localized deposition. A mesh 192 external saddle coils, supervised...
Statistical features of "bursty" behaviour in charged and neutral fluid turbulence, are compared to statistics intermittent events a GOY shell model, avalanches different models Self Organized Criticality (SOC). It is found that inter-burst times show power law distribution for turbulent samples the property which shared only particular case running sandpile model. The breakdown self-similarity generated by isolated observed samples, well reproduced while it absent all SOC considered. On...
In the framework of program for construction—in Padova, Italy—of first prototype International Thermonuclear Experimental Reactor 1 MeV–16 MW negative neutral beam injector (NNBI), an R&D activity on voltage holding in vacuum has been initiated since 2009, aimed at supporting design, construction, and development NNBI accelerator. For this purpose, high-voltage Padova test facility, designed to operate up 800 kV, built, parallel a multivoltage multielectrode prediction model (VHPM). This...
The momentum balance has been applied to the ExB flow in edge region of a reversed field pinch (RFP) configuration. All terms, including those involving fluctuations, have measured stationary condition Extrap-T2R RFP experiment. It is found that component Reynolds stress driven by electrostatic fluctuations term playing major role driving shear value marginal for turbulent suppression, so results are favor turbulence self-regulating mechanism underlying at edge. Balancing sheared and damping...
Localized heating has been observed in unexpected positions on anodic surfaces a multi-electrode device insulated by vacuum gaps. In double polarity experiments, counter-intuitive behavior of current-voltage characteristic also observed. The phenomena could depend cascade effect charged particles exchanged between electrodes and mutual correlation particle trajectories electrode occurring during the high voltage conditioning phase. Attractors regions ascribed to regenerative processes...
Study of High DC Voltage breakdown between stainless steel electrodes separated