Compact Neutron Generator Technology

Models: JNG-2-DD/DT &

JNG-3-DD/DT

---Robert Goldstein Technical Associates, North American Distributor

OVERHOFF TECHNOLOGY

A Brief Overview of

Neutron Sources

Naturally Occurring/EnvironmentalCosmic

The Solar Wind. High energy charged particles which hit nuclei

in the earth’s atmosphere creating secondary particles including neutrons. Intensity varies inversely with solar activity.

Terrestrial Spontaneous fission mostly U-238, less than 10% naturally

induced U-235 fission. 232 Cf

A Brief Overview of

Neutron Sources

Intentional Radioisotope sources Photoneutron Sources Accelerator sources Nuclear reactors Spallation sources Neutron generators

A Brief Overview of

Neutron Sources

Intentional Radioisotope sources

252 Cf SP ½ life 100yr, E(n) 2.3MeV

Table 1.1 Properties of commonly used (ũ,n) sources

Source Ea (MeV) T 1/2 Yield (n/a)

210Po+BE 5.30 138.4 days 0.7 x 10-4

226Ra+Be 4.78, 4.59 1.622 x 10 3 years 1.8 x 10-4

239Pu+Be 5.15 2.44 x 10 4 years 0.6 x 10-4

241Am+Be 5.48 4.60 x 10 2 years 0.7 x 10-4

242Cm+Be 6.11 163 days 1.1 x 10-4

241Am+B 5.48 2.44 x 10 4 years 1.0 x 10-5

241Am+F 5.48 2.44 x 10 4 years 4.0 x 10-6

A Brief Overview of

Neutron Sources

Intentional Photoneutron Sources

Table 1.2 Properties of commonly used photoneutron sources

Source E7 (MeV) T 1/2 Yield (n/β) cm 2 gm -1

24Na+Be 2.757 15.1 h 3.8 x 10-6

24Na+D2O 2.757 15.1 h 7.3 x 10-6

72Ga+D2O 2.51 14.3 h 1.9 x 10-6

124Sb+Be 1.691 60.9 days 5.1 x 10-6

140La+Be 2.51 40.2 h 0.08 x 10-6

Radioisotope decay with Gamma energy exceeding the neutron binding energy of a nucleus can eject a Be or D2 neutron, called a photo-neutron

A Brief Overview of

Neutron Sources

Intentional Accelerator Sources

The simplest way to use an accelerator to generate neutrons is to use the bremsstrahlung from electron accelerators such as synchrotron or beta tron to produce photoneutrons. This gives a continuous energy distribution which is not very useful.

Pulsed electron linacs can also be used, for example electron bombardment of Uranium can produce 30MeV neutrons.

A Brief Overview of

Neutron Sources

Intentional Nuclear reactors and Spallation sources

Are beyond the scope of this presentation.

A Brief Overview of

Neutron Sources

Intentional Neutron Generators

A subset of the accelerator category which are also fusion devices.

First used in 1933. These small electrostatic accelerators use one of two

exothermic reactions (produces energy): D + 2H --> 3He3 + n 3.26 MeV D + 3H --> 4He3 + n 17.6 MeV

A Brief Overview of

Neutron Sources

IntentionalNeutron Generators A Metal Hydride Target is UtilizedAfter the Reaction: The He and n travel in opposite directions producing high neutron yields. Energy at different angles is given by:

4En = En d +2(2 En Ed )1/2cos Θ = 3Q

JNG-2 – Neutron GeneratorBenefits:

Portability Reduced Power Input Requirements Increased Neutron Output Adaptable for Tailoring to Specific

Customer Needs. Reduced Manufacturing Costs High Reliability and Long Operating Life

Applications: Non-Destructive Testing

Homeland Security / Military Nuclear Industry Mining and Drilling Medicine Civil, Aeronautical, & Nautical Engineering Research Laboratories

Typical Target Based Neutron Generators versus JNG-2

Typical Neutron Generators JNG-2

Design Complicated with Many Electronic and Physical Components

Simple, mechanically based

Power Consumption Tens of Kilowatts 90 Watts

Neutron Output 10*6 n/s to 10*8 n/s at applied voltages in the range of hundred kV+

DD – 1*105 n/s

DT – 1*107 n/s

Case Diameter Varies 13 cm

Case Length Varies 65 cm

Weight 33 lbs – 362 lbs 28 lbs

Operation Deuterium – Deuterium – DD

Deuterium – Tritium - DT

Deuterium – Deuterium – DD

Deuterium – Tritium - DT

Projected Lifetime 1,200 hours – 4,000 hours 3-5 Years with Option to Refuel and Service at End Time

Neutron Generator – Basic Process

Homeland Security / Military

Detection of Explosives & Fissile Material in Cargo or Luggage

Chemical Analysis of Questionable Contents

Land Mine Detection Shipping Container Evaluation Narcotics Detection

Nuclear Industry

Compliance with the GALL Report

NUREG-1801 (2010)

Measuring Radiation Structural Damage

Containment Vessels

Cooling Pools

Pipes

Nuclear Industry

Generic Aging Lessons Learned (GALL)The GALL report evaluates existing programs for providing structural and component safety in Nuclear Power Plants. As these plants age and come up for renewal the GALL report facilitates the renewal process.

Its focus is on the staff review on the augmented existing programs for license renewal. Incorporation of the GALL report into NUREG-1800 and 1801 improves efficiency of the license renewal process.

Mining & Drilling

Oil Well Logging On-Line Assaying

of Materials i.e. Coal, Cement, etc

Borehole Logging Fuel Reprocessing Mining of a Wide

Variety of Minerals

Medicine Neutron

Radiography Neutron

Spectroscopy Neutron

Brachytherapy Boron Neutron

Capture Therapy (BNCT)

Civil, Aeronautical, & Nautical Engineering

Structural Inspection Gas & Oil Tank

Walls Bridge Integrity Airplane/Ship

Components Piping

Research Laboratories

Material Science

Nano Technology

Non-Invasive Analysis

Specifications for JNG-2 & JNG-3

JNG-2 DD & DT JNG-3 DD & DT

Neutron Output: 105 n/s using D-D

107 n/s using D-T

106 n/s using D-D

108 n/s using D-T

Neutron Energy 2.45 Mev using D-D

14 MeV using D-T

2.45 Mev using D-D

14 MeV using D-T

Cooling System Air Convection Air Convection

Voltage 45kV 65kV

Current 2mA 5mA

Power Consumption 90 W 325 W

Maximum Input Power 250 W 250 W

Length 65 cm 65 cm

Diameter 13 cm 13 cm

Total Weight 13 kg 13 kg

Projected Lifetime 3-5 Years with Option to Refuel and Service at End Time

3-5 Years with Option to Refuel and Service at End Time

Replaces Need for 252Cf Sources & Other Radioisotpe Sources

Safer to Operator Safer to the Public Eliminates Storage Issues of Source

Material No risk of theft of radioactive material

Additional Benefits of the

JNG-2 and JNG-3

Ideal for Calibrating Neutron Detectors for Spontaneous Fission Neutrons

Calibrate Neutron Detectors for Higher Energies Including AmBe when Energy Correction Factor is established

JNG-2-DT Produces 14.1 MeV Neutrons and is available as a Neutron Interrogator

Certification

This instrument has been tested and certified by independent university tests at

the University of Sydney, Australia

Neutron Generators

Table 1.1 and 1.2Neutrons, Nuclei and Matter; An Exploration of

the physics of Slow NeutronsBy James Byrne (1994)