The NSD neutron generator is an improvement to the spherical Inertial Electrostatic Confinement (IEC) device. It provides a linear geometry source.

IEC is the simplest way to achieve sustained nuclear fusion. While the possibility to scale the technolgy up to achieve more power output that input can be debated, there is no doubt that the technology provides a credible neutron generator without the disadvantages of a solid target.

IEC fusion is briefly illustrated below.

A hollow transparent grid cathode (-) is surrounded by anode (+) at ground potential.
Applying a very high voltage to a low pressure gas will induce a glow discharge.

The positive ions (shown as red spot) are attracted to the cathode. Ideally an ion will be channeled by the electrostatic focusing to pass through the the cathode grid aperatures. If there were to be no collisions with other ions and neutral particles the ion may oscillate.

In reality the low pressure gas-plasma is still very dense so that there will be collisions of various types. Despite such energy loss mechanisms sufficient ions do get accelerated to kinetic energy levels over ~ 15 keV where fusion collisions can occur. The greater the applied voltage on the glow discharge, the greater is the probability of a fusion collision.

With sufficient numbers of ions , charge space effects can have an influence on the ion trajectories in the central volume. The animation below illustrates that a virtual anode forms by the self organisation of the high density ion population. The virtual anode has a positive charge that is great enought to deflect the ions and effectively keep them in the central region. These ions contribute their positive charge to the charge space which is self destributing into a shell of positive charge space.

This plasma structure confines the ions at kinetic energies where fusion collisions may occur. The longer confinement time increases the fusion rate more than a simple increase of the applied electric current. With pulsed current at high voltage the superlinear scaling becomes most apparent with much greater neutron emission rates.

Fusion of the hydrogen isotopes Deuterium or Tritium produces a large particle and a neutron. The neutron is able to escape from the reaction chamber.

Note that this process is occuring 10⁶ to 10¹¹ times per second in typical NSD neutron generators.

NSD has developed a unique linear geometry neutron generator. This may be envisaged as a fluorescent light tube but emitting neutrons. It is not a linear accelerator. It is not a derivative of a nuclear weapon "trigger". It is not "another short lived sealed tube neutron generator". There is no solid target.

The sealed device is very robust and reusable.

The length of the neutron emission zone may be specified by the customer. The shortest practical length is 25 mm. A typical length is 350 mm. Longer electrodes are feasible.

A typical application may be Online Analysis of bulk materials quality monitoring and for chemical process control.

Gamma detectors

Mineral stream on a conveyor belt

Linear neutron emission zone

A vital feature of our neutron generator technology is that it has radically longer operational lifetime which is an essential requirement for industrial applications. The running lifetime is measured in years rather than hundreds to a few thousand hours as offered by the conventional neutron generators. There is no solid target to erode and cause failure of the sealed reaction chamber. The Deuterium fuel depletion may be the first reason for servicing a well used unit.

Indeed we are quite confident in stating that our neutron generator has the longest life in its class. Our experience with the Mk0 development showed by means of a life test unit that 7,000 hours could be reached easily and that 10,000 or even 20,000 was likely. Our competitors offer 3,000 and 4,000 hour lifetimes.

The new Mk1 development has shown that the improved aging mitigation features that we have designed do indeed work. More recently we were able to conduct an accelerated life test by using a relatively high vapour pressure metal for the cathode. It partially vapourised and the metal deposits failed to stop the neutron generator. So we are confident that a life test will easily demonstrate 25,000 hours or much more. This is essential for an economically viable system life cycle cost.

We have developed a fully automated control system algorithm that was proven via the Mk0 life test experience. The new implementation has further improvements. The fully automated control unit handles contingencies as well as ensuring consistent output performance.

Indeed the automation enables a substitution of isotope sources. This may cause radiation safety authorities some confusion since a fully automated electrically powered neutron generator is a new class of neutron source that is neither a radionuclide nor an accelerator which requires expensive technician operators. It can be integrated into systems which may satisfy the radiation safety requirements for unattended continuous operation in industrial environments.

The neutron generator system may be engineered into various packaging formats to suit OEM requirements.

Single unit projects for laboratories and prototype requirements can be developed.

The High Voltage Power Supply is packaged in a 19" rack flange enclosure.

The Central Control Unit may be 19" rack mounted enclosure or an enclosure similar to the prototype shown in some pictures.

See the Geometry page.

Air cooling is used. It is cheap and reliable.

Future higher power systems may use water or other fluid cooling sub-systems.

See the Performance page.