Dan M Timus | PubMed Health

PubMed2005

Energy behavior of neutrons around axi-symmetric sealed-off neutron generating tubes.

The aim of this paper is to contribute to analytical characterization of the spatial dependency of the mean energy of fast neutrons produced in non-dispersive media by sealed-off neutron generating tubes (NGT) having axial symmetry. Neutrons are generated in most of NGT by accelerating a mixture of hydrogen isotope ions (deuterons and tritons) onto plane self-targets. Deuterons and tritons are implanted in the mentioned targets and become target nuclei for the subsequent incoming ions. d-T, t-D and d-D fast neutrons are generated. Analytical expressions for the neutron mean energy in these three cases are deduced, taking into account the exothermic character of the reactions. Due consideration is paid to collision kinetics, depending upon mass and kinetic energy of particles involved in the nuclear reaction, nuclear reaction energy, etc.

Journal Article↗

PubMed2005

Plane rectangular tritium target response to excitation by uniform distributed normal accelerated deuteron beam.

This work is a contribution to analytical study of the spatial dependency of the d-T mean neutron energy in the vicinity of a homogeneous tritium-occluded rectangular plane target. An accelerated deuteron beam excites the tritium target with normal incidence to the target plane. The transverse density of accelerated deuteron beam is assumed to be constant close to the target. Due consideration being paid to d-T collision kinetics, depending upon mass and kinetic energy of particles involved in the nuclear collision, nuclear reaction energy, etc, in particular circumstances, the elementary neutron energy emission in non-dispersive media can be considered to be omni-directional or very low anisotropical. Consequently, analytical expressions can be considerably simplified, taking into account the exothermic character of d-T fusion reaction. A number of expressions for energetic prediction of the fast neutron generated, in this case, by d-T reaction are proposed. Animated three-dimensional-graphics is suggested. Computationally tractable tools are of importance in the study of some situations such as induced reactions and activation analysis using 14MeV neutrons, investigations in health-physics, radiation dose characterization, nuclear medicine, damage effects, and simulation studies.

Journal Article↗