The nonexponential relaxation occurring in complex dynamics manifested in a wide variety of systems is analyzed through a simple model of diffusion in phase space. It is found that the inability of the system to find its equilibrium state in any time scale becomes apparent in an effective temperature field, which leads to a hierarchy of relaxation times responsible for the slow relaxation pheno...

The first toroidal, gyrokinetic, electromagnetic simulations of small scale plasma turbulence are presented. The turbulence considered is driven by gradients in the electron temperature. It is found that electron temperature gradient (ETG) turbulence can induce experimentally relevant thermal losses in magnetic confinement fusion devices. For typical tokamak parameters, the transport is essenti...

Global electrostatic ITG turbulence physics, together with background dynamics, has been simulated in realistic tokamak core geometry using XGC1, a full-function 5D gyrokinetic particle code. Adiabatic electron model has been used. Some verification exercises of XGC1 have been presented. The simulation volume extends from the magnetic axis to the pedestal top inside the magnetic separatrix. Cen...

Introduction: Measurement of Apparent Diffusion Coefficients (ADC) of hyperpolarized He gas in the lungs, can provide information on the micro-anatomical changes associated with disease over length scales permitted by the diffusion time. Improved sensitivity of ADC to chronic obstructive pulmonary disease (COPD) has recently been demonstrated using diffusion times on the order of seconds. These...

Aims. We investigate the electron temperature gradient in the galactic disk as measured by young HII regions on the basis of radio recombination lines and the corresponding gradient in planetary nebulae (PN) based on [OIII] electron temperatures. The main goal is to investigate the time evolution of the electron temperature gradient and of the radial abundance gradient, which is essentially a m...

In conventional spin echo (SE) imaging, the longitudinal magnetization (that is generated by the presence of the main magnetic field, B0) is tipped into the transverse plane using a radiofrequency (RF) pulse that tips the magnetization 90 degrees. Once in the transverse plane, the magnetization rotates, or precesses, around the axis of the main magnetic field. As the transverse magnetization pr...

We carry out a theoretical investigation to clarify the dynamic property of photo-created nano-sized ferroelectric cluster observed in the paraelectric BaTiO3 as a real time correlation of speckle pattern between two soft X-ray laser pulses, at just above the paraelectricferroelectric phase transition temperature. Based on a model with coupled soft X-ray photon and ferroelectric phonon mode, we...

The electron and phonon temperature distribution in semiconductors initially heated on the surface with a short laser pulse is calculated as a function of position and time. We solved the coupled one-dimensional heat diffusion equations for electron and phonon systems in the linear approximation in which the physical parameters of the sample are temperature independent. We also consider the hea...

We present BTE-Barna (Boltzmann Transport Equation - Beyond the Rta for NAnosystems), a software package that extends Monte Carlo (MC) module of almaBTE solver Peierls-Boltzmann transport equation phonons (PBTE) to work with nanosystems based on 2D materials complex geometries. To properly capture how phonon occupations evolve in momentum space as result scattering, we have supplemented relaxat...

We have completed an extensive study of Xe longitudinal spin relaxation in the gas phase, involving both intrinsic and extrinsic mechanisms. The dominant intrinsic relaxation is mediated by the formation of persistent Xe2 van der Waals dimers. The dependence of this relaxation on applied magnetic field yields the relative contributions of the spin-rotation and chemical-shift-anisotropy interact...