Spectral cascade and energy dissipation of Alfven turbulence is studied using a massively parallel gyrokinetic particle simulation. The simulation observes a magnetic energy spectrum with a power law index of ”-5/3” in the long wavelength, which agrees with magnetohydrodynamic results in the inertial range. In the dissipation range, the simulation finds a spectral break point on the ion gyrorad...

Action-angle representation of linear fluctuation in plasma is formally performed by taking the Lagrange-Hamilton theory as the basis and invoking the recent spectral technique [Hirota and Fukumoto, J. Math. Phys. 49 083101 (2008)], which is shown to be applicable equally to the magnetohydrodynamic (MHD) system and the Vlasov-Maxwell system. This formalism leads to a natural definition of the w...

We present a quantitative estimate of the anisotropic power and scaling of magnetic field fluctuations in inertial range magnetohydrodynamic turbulence, using a novel wavelet technique applied to spacecraft measurements in the solar wind. We show for the first time that, when the local magnetic field direction is parallel to the flow, the spacecraft-frame spectrum has a spectral index near 2. T...

Recent observational evidence for magnetic field direction effects on helioseismic signals in sunspot penumbrae is suggestive of magnetohydrodynamic (MHD) mode conversion occurring at lower levels. This possibility is explored using wave mechanical and ray theory in a model of the Sun’s surface layers permeated by uniform inclined magnetic field. It is found that fastto-slow conversion near the...

Background 12-lead Electrocardiogram (ECG) is a clinical standard for patient physiological monitoring. An MRI-conditional 12-lead ECG should permit detection of acute myocardial ischemia during MR imaging or MRI-guided therapy, which may improve the handling of patients with ischemic histories. MRI visualization of ischemic episodes can also enhance the understanding of ischemic progression. P...

Interaction of a shockwavewith a current sheet is investigated by the two-dimensional numerical magnetohydrodynamic model. In accordance with the solar coronal conditions, the ratio of the thermal to magnetic pressures of 0.1 and the shock Alfven Mach number of about 1.25 are used. It is found that the shock wave initiates magnetic reconnection process in the current sheet. Further, it is found...

Magnetohydrodynamic (MHD) turbulence in the solar wind is observed to show the spectral behavior of classical Kolmogorov fluid turbulence over an inertial subrange and departures from this at short wavelengths, where energy should be dissipated. Here we present the first measurements of the electric field fluctuation spectrum over the inertial and dissipative wave number ranges in a Beta > or a...

We study the connection between the long-time dynamics of the 3D magnetohydrodynamicα model and the exact 3D magnetohydrodynamic system. We prove that the trajectory attractor Uα of the 3D magnetohydrodynamic-α model converges to the trajectory attractor U0 of the 3D magnetohydrodynamic system (in an appropriate topology) when α approaches zero.