Nuclear Radiation Detection for the Natural Environment

Abstract

thinking of 1 to the neutrc Liquid scintillators, proportional counters, well as air? nuclear emulsions, etched track detectors, and anything to i thermoluminescent crystals have been used to meatrum--right d sure the enviromental neutron flux from thermal tions had bee to 10 MeV energies, below ground, at ground level, and Bethe in at an air-water interface, on a tower, and at an airborne altitude of 20,000 feet. Results are As a res compared with calculations based an a modified came involvec program for reactor computations.generaticn of this effect c

The effects of a hydrogen-rich ground cover on cosmogenic thermal neutrons: Implications for exposure dating

“…the neutron energy spectrum remains essentially unchanged (Goldhagen et al, 2003;Goldhagen et al, 2002;Kowatari et al, 2005;Lal and Peters, 1967). However, near the Earth's surface both neutron production and scattering properties change profoundly, leading to a non-equilibrium situation (Hendrick and Edge, 1966;Kastner et al, 1970;Kodama, 1983;Masarik et al, 2007;O'Brien et al, 1978). In particular, the flux of thermal neutrons increases dramatically, by approximately one order of magnitude, due to increased production in the solid Earth and effective moderation by water/moisture at the ground level (Hendrick and Edge, 1966;Kastner et al, 1970;Kodama, 1983;Masarik et al, 2007;O'Brien et al, 1978).…”

“…However, near the Earth's surface both neutron production and scattering properties change profoundly, leading to a non-equilibrium situation (Hendrick and Edge, 1966;Kastner et al, 1970;Kodama, 1983;Masarik et al, 2007;O'Brien et al, 1978). In particular, the flux of thermal neutrons increases dramatically, by approximately one order of magnitude, due to increased production in the solid Earth and effective moderation by water/moisture at the ground level (Hendrick and Edge, 1966;Kastner et al, 1970;Kodama, 1983;Masarik et al, 2007;O'Brien et al, 1978). This perturbation of the thermal neutron flux is measurable up to 100 m above ground (Hendrick and Edge, 1966); the attenuation of this perturbation occurs due to the large reaction cross section of 14 N for thermal neutrons and the high abundance of nitrogen in air (Hendrick and Edge, 1966).…”