Here, we are concerned with a new, highly precise, numerical solution to the one-dimensional neutron transport equation based on Case’s analytical, singular eigenfunction expansion (SEE). While considerable number of solutions currently exist, understandably, because its complexity even in one dimension, there only few truly analytical equation. In 1960, Case introduced consistent theory SEE fo...

The current picture of the collapse and explosion of massive stars and the formation of neutron stars is reviewed. According to the favored scenario, however by no means proven and undisputed, neutrinos deposit the energy of the explosion in the stellar medium which surrounds the nascent neutron star. Observations, in particular of Supernova 1987A, suggest that mixing processes play an importan...

Reactor noise, caused both by the probabilistic nature of the fission chains and external reactivity noises, is one of the basic topics in nuclear science and engineering, both in theory and practice. Modeling reactor noise (and neutron flux fluctuation in general) is traditionally performed by two main approaches: the stochastic transport equation for the probability generating function and th...

We calculate the logarithmic moment of the phonon frequency spectrum at a single density for 29 monatomic liquids using two methods, both suggested by Wallace's theory of liquid dynamics: The first method relies on liquid entropy data and the second on neutron scattering data in the crystal phase. This theory predicts that for a class of elements called "normal melters," including all 29 of the...

We present the results of Newtonian hydrodynamic simulations of the coalescence of a binary consisting of a black hole with a neutron star. The calculations show that for a wide range of initial conditions the core of the neutron star survives the initial mass transfer episode. We therefore identify black hole–neutron star binaries as the astrophysical production site of low mass neutron stars ...

The core model DYN3D which has been developed for three-dimensional analyses of steady states and transients in thermal reactors with quadratic or hexagonal fuel assemblies is based on nodal methods for the solution of the two-group neutron diffusion equation. Loading cores with higher content of MOX fuel, the increase of the fuel cycle length and new types of reactors are challenging for these...

The experimental results on DDX (double differential neutron production cross section data), TTY (thick target neutron production yield data), heavy-ion produced neutron transport data, and spallation products production cross section data taken at Heavy Ion Medical Accelerator (HIMAC), National Institute of Radiological Sciences (NIRS), Japan, are presented for heavy ions of He to Xe in the en...

Abstract-A half-range orthogonality theorem concerning the established elementary solutions of the two-group neutron transport equation for isotropic scattering and plane geometry is proved. The orthogonality relations are based on a Chandrasekhar-type H-matrix, and all necessary normalization integrals are evaluated so that the desired expansion coefficients may be expressed concisely in terms...

A general thermodynamic argument shows that multi-component matter in full chemical equilibrium, with uniform entropy per baryon, is generally stably stratified. This is particularly relevant for neutron stars, in which the effects of entropy are negligible compared to those of the equilibrium composition gradient established by weak interactions. It can therefore be asserted that, regardless o...