The radiation power loss from a magnetically confined plasma in a stellarator has been calculated using neoclassical particle and energy fluxes in an energy balance equation. We could obtain a power loss of about 34% of the total input power by numerical calculation. This fraction of the power loss has been found to be in good agreement with the experimentally measured values of 30-40% for...

The quasi-elastic neutron scattering (QENS) technique was first used to derive self-diffusivities of hydrocarbons in zeolites, but transport diffusivities of deuterated molecules and of molecules which do not contain hydrogen atoms can now be measured. The technique allows to probe diffusion over length scales ranging from an Å to hundreds of Å. The mechanism of diffusion can thus be followed f...

In this paper a new analysis of the characteristics and propagation of random fluctuations in Monte Carlo (MC) eigenvalue calculations is presented. In particular, random fluctuations in the fission source distribution produced from a fixed set of initial neutron source locations are considered. Unlike previous analyses, this work relies on spectral theory to analyze a general class of MC eigen...

We present an approach to uncertainty quantification for nuclear applications, which combines the covariance evaluation of differential cross-sections data and the error propagation from matching a criticality experiment using a neutron-transport calculation. We have studied the reduction in uncertainty of Pu fission cross sections by using a one-dimensional neutron-transport calculation with t...

Thermal motion of nuclides has a significant effect on the reaction probabilities and scattering kinematics of neutrons. Since also the nuclides in nuclear reactor materials are in constant thermal motion, the temperature-induced effects need to be taken into account in all neutron transport calculations. This task is notably complicated by the fact that the temperature distributions within ope...

a new derivation of the quantum boltzmann transport equation for the fermion system from the quantum time evolution equation for the wigner distribution function is presented. the method exhibits the origin of the time - irreversibility of the boltzmann equation. in the present work, the spin dependent and indistinguishibility of particles are also considered.

the radiation power loss from a magnetically confined plasma in a stellarator has been calculated using neoclassical particle and energy fluxes in an energy balance equation. we could obtain a power loss of about 34% of the total input power by numerical calculation. this fraction of the power loss has been found to be in good agreement with the experimentally measured values of 30-40% for our ...

We develop a new theory of volumetric light transport for media with non-exponential free-flight distributions. Recent insights from atmospheric sciences and neutron transport demonstrate that such distributions arise in the presence of correlated scatterers, which are naturally produced by processes such as cloud condensation and fractal-pattern formation. Our theory accommodates correlations ...

Recent progress to treat clustering in nuclear systems has an impact different branches of theory. Numerical methods as well many-body theory (Green-function methods) have been worked out describe few-body clusters a environment where medium effects, particular the antisymmetrization wave function (Pauli blocking) are relevance. Nuclear structure (Hoyle – like states), reactions, and consequenc...