Li-Foil Multiwire Proportional Counter (MWPC) Neutron Detector

Li-Foil MWPC Neutron Detector Technology

A Low-Cost Large-Area Neutron Detector

Size matters and so does weight. The innovative Li-Foil Multi-wire Proportional Counter (MWPC) Neutron Detectors are just 0.7 kg (1.6 lbs) and are an affordable large-area alternative to the ³He-based detectors and much safer than BF₃. They maintain a high thermal-neutron detection efficiency, at a comparable volume, mass, voltage, and power required. The technology has the flexibility to easily adjust available detection area to customer specifications with a 20% to 70% (40% standard) thermal-neutron detection efficiency. The Li-Foil MWPC are being integrated into existing electronics technology as replacements for ³He and BF₃-based detectors. Li-Foil offers a lightweight solution while maintaining the high neutron detection sensitivity and ruggedness that are known of ³He-based detectors.

Eliminate the high voltage circuitry and interfacing hassle with ³He and BF₃-based detectors.  The Li-Foil provides several connector types, USB, M8 or SMA while needing just nominal 3V power to operate.  No more setting high voltage or pulse shaping with the Li-Foil as HV is generated on-board and the output is TTL or digital USB. 

The following plot includes a normalized thermal-neutron reaction-product pulse height spectrum from Cf-252 at 1.5 meters from a Li-Foil MWPC backpack device. Background was collected in the same configuration, shown in blue. Gamma-ray rejection is inherent to the device design where the response to 50mR / Hr of Cs-137 662 keV gamma rays is shown in the gray curve. Monte Carlo N-Particle Transport (MCNP) response to Cf-252 modeled in an equivalent Li-Foil MWPC testing configuration is shown in the dotted line.

Electronics & Interfacing

• Optional onboard readout electronics include pulse processing components (e.g. preamp, amp, etc.) with TTL output or output driven signal to interface with customer’s GUI.
• Customizable connection interface - i.e. USB, M8, SMA, etc.
• Optional microphonics rejection integrated into the electronics firmware

Interface Connector Options

Readout electronics can be outfitted with an M8 style waterproof connector (3.3V square pulse signal), USB-B (USB Communications Device Class), or other custom interface upon request.

Technical Specifications

*Gamma-Ray Rejection Ratio

**Thermal-Neutron Detection Efficiency 

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