Subjects: Physics >> Physics of Gases, Plasmas, and Electric Discharges Subjects: Mathematics >> Mathematics (General) submitted time 2022-12-27
Abstract: For 3D vector fields, the governing formula of invariant manifolds grown from a hyperbolic cycle is given in cylindrical coordinates. The initial growth directions depend on the Jacobian matrices of Poincaré map on that cycle, for which an evolution formula is deduced to reveal the relationship among Jacobians of different Poincaré sections. The evolution formula also applies to cycles in arbitrary finite $n$-dim autonomous continuous-time dynamical systems. Non-Möbiusian/Möbiusian saddle cycles and a dummy X-cycle are constructed analytically as demonstration. A real-world numeric example of analyzing a magnetic field timeslice on EAST is presented.
Peer Review Status:Awaiting Review
Subjects: Physics >> Physics of Gases, Plasmas, and Electric Discharges Subjects: Physics >> Interdisciplinary Physics and Related Areas of Science and Technology Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2019-03-31
Abstract: In plasma turbulence, such as the solar wind, the helical and (nearly) periodic structures are not necessarily linear waves. Plasmas in different environments present different dynamical characters, admitting various nonlinear structures. It is presented here two alternative nonlinear mechanisms that lead to relevant chirality issues in solar wind, the helical turbulent modes and breathers. The former is explained by revisiting a recent proposal in studying solar wind with the extended magnetohydrodynamics, and the latter is argued with a list of sources of information from water waves, plasmas and Bos\'e-Einstein condensates, though a concrete solar wind model for it is still open. "
Peer Review Status:Awaiting Review
Subjects: Physics >> Physics of Gases, Plasmas, and Electric Discharges submitted time 2018-06-07
Abstract: A detailed analysis of the synchrotron radiation intensity and energy of runaway electrons are presented for EAST. In order to make the energy of the calculated runaway electrons more accurate, we take the shafranov shift into account. The results of the analysis show that the synchrotron radiation intensity and energy of runaway electrons did not reach the maximum at the same time. The energy of runaway electrons reached the maximum value first, and then the synchrotron radiation intensity of the runaway electrons reached the maximum. We also analyzed the runaway electrons density, and it shows the density of runaway electrons continuously increased. For this reason, although the energy of the runaway electrons drops but the synchrotron radiation intensity of the runaway electrons will continue rising for a while
Peer Review Status:Awaiting Review
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics Subjects: Physics >> Physics of Gases, Plasmas, and Electric Discharges submitted time 2017-11-27
Abstract: An important feature of China Fusion Engineering Test Reactor(CFETR) project is represented by the additional heating obtained from the injection of neutral beams based on accelerated negative ions. For the neutral beams based on negative ions, the most important measurements are beam uniformity, beamlet divergence and stripping losses. According to the CFETR requirement, the maximum allowed beam divergence angle and beam non-uniformity are 6 mrad and ±10%,respectively. As 1D carbon tiles have large ratio between perpendicular conductivity and parallel conductivity and high stability, they can be used for beam uniformity and beamlet divergence measurement. This paper presents the investigation of the influence on the response of 1D carbon tile having the thermal characteristics and features of some dedicated diagnostics. Simulations show that it will be possible to verify experimentally whether the beam meets the requirement about the maximum allowed value. This work lays a foundation for design and application of high precision beam diagnostic targets.
Peer Review Status:Awaiting Review
Subjects: Physics >> Physics of Gases, Plasmas, and Electric Discharges submitted time 2017-09-03
Abstract:We propose a more effective fluid description on Vlasov-Maxwell (V-M) system. It is via an open set of off-center moments, which obey an open set of motion equations.This new description is of more advantage to give exact macroscopic information of the V-M system than the well-known moments-description. The new description implies that obtaining exact solutions of all moments is not necessary condition of obtaining those of self-consistent fields. 我们对Vlasov-Maxwell系统提出一更有效的流体描述。该描述通过一开放的偏心矩系列。该偏心矩系列服从一开放的流体方程组。与著名的矩描述相比,该新描述更具有优势去获得准确的V-M系统的宏观信息。该新描述意味着所有矩的准确解不是自洽场准确解的必要条件。
Peer Review Status:Awaiting Review