In phase I of this project, we demonstrated that effective Boron enrichment could result in a five-fold stopping power improvement in detection capabilities using ¹⁰B₄C sputtering targets and a 1-meter, PTI detector module.

In phase II, we will further develop and utilize this production methodology to manufacture a 22 module, 1 m² single layer detector capable of maintaining this five-fold higher stopping power. We propose a detector technology that is based on closely-packed arrays of boron-coated, aluminum straws.  The square-meter panel detector satisfies SNS requirements and consists of several thousand, independently read-out straws to allow higher detection efficiency over a larger detection area.  This innovative straw technology also supports high event rates, discriminates effectively against gamma rays, and generates 3D position data.

The Spallation Neutron Source (SNS) facility recently announced plans to ramp up to 1 megawatt operation in coming months.  This ramp up will push available thermal neutron flux at least an order of magnitude above that achievable at any other neutron science facility. Fundamental detector improvements are necessary to handle the markedly increased deliverable flux as current imaging detectors at many target stations will be insufficient and overwhelmed.  Additionally, ³He gas cannot support large deployments, due to the isotope’s very limited availability on Earth.  The SNS requirement for 75 m² detectors, and increasing demand for detection security in general, makes finding alternative detection technologies imperative. By contrast, the ¹⁰B isotope is extremely plentiful, inexpensive, and can meet a very significant need in neutron detection. 

PTI has proposed a detector technology that is based on 10-Boron Carbide thin film conversion of neutrons. Reaction products are then detected in the gas of a thin straw detector. Through the use of densely packed straw arrays: often as long as 1 meter in length, efficient high resolution imaging can be achieved with a quantum leap in integral and differential counting rate. This endeavor builds upon a previously, successful DOE project where we developed a complete 1 m² neutron straw imaging system which also utilized a natural Boron Carbide straw coating.

To round out the technology, PTI is also developing an in-house system for creating large production quantities of Boron-coated foil. Through the development of an exceptionally economical reel-to-reel production technique, these straw-based imaging detectors can be produced at a fraction of the cost of current ³He- based detectors.