In this electronic article we use the one-dimensional multigroup neutron diffusion equation to reconstruct the neutron flux in a slab reactor from the nuclear parameters of the reactor, boundary and symmetry condition, initial flux and . The diffusion equation was solved analytically for one single homogeneous fuel region and for two regions considering fuel and reflector. To validate the metho...

The CITATION code based on neutron diffusion theory is used for flux calculation inside voluminous sample in prompt gamma activation analysis with an isotopic neutron source (241Am–Be). The code used the specific parameters related to energy spectrum source, irradiation system materials (shielding, reflector, etc.), geometry and elemental composition of the sample. The flux distribution (therma...

INTRODUCTION : The most informative neutron scattering investigations of the atomic-scale dynamical properties of crystalline solids nearly always require single crystal samples and – to date have mostly been carried out on crystal spectrometers at high-flux, reactor-based, steady-state neutron sources. Because such measurements tend to be made with small samples and are invariably flux-limited...

The neutron flux induced by radioactivity at the Gran Sasso underground laboratory is revisited. We have performed calculations and Monte Carlo simulations; the results offer an independent check to the available experimental data reported by different authors, which vary rather widely. This study gives detailed information on the expected spectrum and on the variability of the neutron flux due...

A newly developed numerical Laplace transform inversion (NLTI) will be presented to determine the transient flux distribution within a subcritical fissile sample. The NLTI considered in this presentation has evolved to its present state over the past 10 years of application. The methodology adopted relies on the evaluation of the Bromwich contour through acceleration of the convergence of an in...

The term ‘thermal flux’ implies a Maxwellian distribution of velocity and energy corresponding to the most probable velocity of 2200 m s−1 at 293.4 K. In order to measure the thermal neutron flux density, the foil activation method was used. Thermal neutron flux determination in paraffin phantom by counting the emitted rays of indium foils with two different detectors (Geiger– Muller counter an...

In the framework of the Neutronic and Nuclear Assessment Task Group of the MEGAPIE experiment we measured the delayed neutron (DN) flux at the top of the target. The measurement was proposed mainly for radioprotection purposes since the DN flux at the top of the target has been estimated to be of the same order of magnitude as the prompt neutron flux. Given the strong model-dependence of DN pre...

The transition to a type II proton superconductor which is believed to occur in a cooling neutron star is accompanied by changes in the equation of hydrostatic equilibrium and by the formation of proton vortices with quantized magnetic flux. Analysis of the electron Boltzmann equation for this system and of the proton supercurrent distribution formed at the transition leads to the derivation of...