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Achieving a sustainable dense plasma source has always been of broad interest. Notably, in microwave discharges, gaining dense uniform plasma has held numerous efforts. In this article, a high-efficiency dual-helical antenna for microwave plasma source to improve the performance of the Alborz Tokamak neutral beam injection (NBI) system is presented. For evaluation and analysis of the designed antenna and a conventional rod antenna, COMSOL Multiphysics software is used. Besides, by feeding the antenna using a 2.45-GHz magnetron in the 20-Pa vacuum steel enclosure and the Argon gas injection, a practical experiment has been conducted. Finally, the plasma with a density of $5.5\times 10^{17}\,\,1/\text{m}^{3}$ and the electric field intensity results show that the designed antenna is an optimal alternative in microwave plasma sources. [ABSTRACT FROM AUTHOR]

In recent years, helicon plasma sources have attracted much attention from scientific centers and industry. In this regard, the power coupling is of particular importance for the production of dense plasma in these systems. Therefore, in order to achieve maximum efficiency in these types of plasma sources, it is necessary to analyze the key parameters affecting plasma power absorption such as magnetic field (50–700 G), gas pressure (1–20 mTorr), radiofrequency power (800–2200 W), and RF frequency (6.28, 13.56, 20.34, and 27.12 MHz) applied to Nagoya antenna. Finding the optimal range of these parameters is one of the key parameters in the design and construction of helicon plasma sources. Therefore, in this article, we investigate the parameters affecting the power absorption mechanisms in these types of plasma sources using a 3-D simulation of the helicon plasma source with the finite-element method. Our findings indicate that absorption mechanisms have different effects on the absorption power due to the option of the most optimal plasma parameters’ value. The results show that changes in absorption power in terms of plasma density are nonlinear and show changes in the mode from E to H and eventually to W. Because of the domination of collisionless mechanism, the absorbed power increases in the pressures lower than 2 mTorr. In addition, at pressures above 2 mTorr, it increases due to the collisional mechanism. Plasma density increases linearly as the magnetic field intensity increases. The density peak is observed at the vacuum chamber edge in low magnetic fields (in the range of 65 G) which represents the Trivelpiece-Gould (TG) mode formation. [ABSTRACT FROM AUTHOR]

This program was designed to introduce a plasma platform to examine the field programmable gate array (FPGA) of the link boards typically used at the CERN’s Large Hadron Collider (LHC). Pulsed plasma systems with accelerating gradient of 1 kV/ $\mu \text{m}$ generate high-intensity, high-energy radiation beams. Single-event upset (SEU) is caused by radiation deposition in the FPGA. In FPGA, the SEU probability for 1-MeV protons and 10-keV X-rays are 0.1 and $2 \times 10^{-9}$ particle $^{-1}$. The number of SEU induced in the Si by 1-MeV proton irradiation at 0.8-V bias computed from simulation in COMSOL Multiphysics was $1.8 \times 10^{5}$. Although more experimental research is needed to identify the underlying mechanisms, pulsed plasma is perceived as being a smart alternative to investigate the error structure in FPGA. [ABSTRACT FROM AUTHOR]

The plasma focus (PF) emerged as a potential prospect to produce radionuclide, but the experimental data are not significant in favor of practical medical radioactivity. Empirical scaling grants a set of magnetic lens to enhance the nuclear activity. The experimental radioactivity of low-energy devices is in the range of kilobecquerel and rises to megabecquerel by optimizing and operating at a few hertz. Magnetically driven ion beam improves the radioactivity to the prescribed value of gigabecquerel for nuclear imaging. Magnetic radioactivity competence scheme reflects the vision that small PF, as a smart alternative to cyclotron, generates medical grade radioactivity. [ABSTRACT FROM AUTHOR]

Timing in peak values shifts slightly between gait trials. When gait data are averaged, part of the standard deviation could be associated with this intertrial variability unless normalization is carried out beforehand. The objective of this study was to determine how continuous curve registration, an alignment technique, can reduce intersubject variability in gait data without altering the original curve characteristics. Gait data were obtained by means of a four-camera high-speed video system synchronized to a force plate. The data for 60 gait trials were collected from 20 young, healthy subjects. Curve registration was applied to hip angular displacement, net moment, and power curves generated in the sagittal plane. Following registration, the peak values increased by an average of 1.2% (0.11 +/- 0.26 degrees) for angular displacement, and by 11.2% (0.11 +/- 0.09 W/kg) for power, while there were no changes for moments. First and second derivatives of the unregistered and registered curves did not display significant differences, and the harmonics were barely affected. Continuous curve registration would thus be an appropriate technique for application prior to any statistical analysis using able-bodied gait patterns.