High yield neutron generators using the DD reaction

Abstract

The Lawrence Berkeley National Laboratory and Adelphi Technology Inc. have developed a series of high-yield neutron generators using the D-D reaction with an axial geometry. They operate with a single ion beam and can have a small origin size useful for immediate moderation and a high concentration of thermal neutrons. The generator uses RF induction discharge to efficiently ionize the deuterium gas. This discharge method provides high plasma density for high output current, high atomic species from molecular gases, long life operation and versatility for various discharge chamber geometries. These generators are open systems that can be actively pumped for a continuous supply of deuterium gas further increasing the generator's expected lifetime. Since the system is open, many of the components, including the target, can be easily replaced. Pulsed and continuous operation has been demonstrated. In either mode of operation these generators have been used for Prompt Gamma Neutron Activation Analysis (PGNAA) and neutron activation analysis (NAA). Carleton University and Heliocentric Technologies are developing an Elemental Analyzer based on this neutron source.

A Dosimetry Study of Deuterium-Deuterium Neutron Generator-based In Vivo Neutron Activation Analysis

“…quasi-monoenergetic neutrons at 2.45 MeV by the fusion reaction 2 H(d, n) 3 He. The Q-value for the reaction is 3.3 MeV, splitting kinetic energy and momentum between the 3 He and 1 n, which yields the aforementioned neutron energy almost consistently at 2.45 MeV (Vainionpaa et al 2013;Bergaoui et al 2014).…”

Technology and Applications of Neutron Generators Developed by Adelphi Technology, Inc

“…Measured values are given in ref. [8]. Adjusting the acceleration voltage is the easiest way to change the yield.…”

“…High density polyethylene (HPDE) has been shown by us and others to be an excellent moderator [8,12]. Since the fast neutrons are emitted roughly isotropically from the titanium target [1], the neutrons must be slowed down in the shortest distance in order to achieve the maximum flux of thermal neutrons.…”

“…Higher atomic conversion efficiencies are achieved using the electron cyclotron resonance (ECR) effect [2][3][4][5][6][7][8]. This source can also achieve plasma densities much higher than Penning or RF-driven ion sources while operating at lower gas pressures.…”

Development of high flux thermal neutron generator for neutron activation analysis

“…The deuteron-deuteron fusion reaction (D-D) has been a utilized extensively in recent years in various Adelphi Technology neutron generators [17,19,4] to produce neutrons without using radioactive material. Without the need for tritium, the design and maintenance of D-D generators are much more simple and flexible, ultimately driving down the cost of very high flux neutron generators.…”