13479782 (Greife). Efficient large scale detectors for gammas and neutrons are needed to provide radiological security at international borders and at other sensitive sites. To date large (sqft dimensions) gamma detectors can be liquid or solid organic scintillators while neutron detection is achieved by a combination of moderating plastic material and 3-He filled proportional counters. As 3-He has become scarce and expensive due to its widespread use in radiological security scanners, alternative detector materials need to be developed with similar or superior performance. The aim is also to reduce the price of the individual detectors to allow a wider distribution and as such aid in improving the global nuclear detection architecture. The project brings together an interdisciplinary team of researchers with backgrounds in chemistry/polymer science and nuclear physics to do basic research on the synthesis of scintillating polymers directed at significant improvement in light output, incorporation of neutron sensitive isotopes as well as reduction in production cost. This project will synthesize new organic-based materials for use as dopants and/or matrices with greatly enhanced energy transfer efficiencies over what is commercially available. This goal will be achieved by: 1. Develop highly fluorescent groups that will be chemically incorporated into the polymer matrix, thus preventing aggregation of the fluorescent groups during processing and/or application that is known to reduce efficiency; 2. Develop highly fluorescent boron (10-B) containing materials that can act as both neutron and alpha/gamma detection groups, and 3. Develop "bulky" 3-D highly fluorescent groups that can be physically mixed into the polymer matrix, but will not migrate or aggregate due to its bulky 3-D structure. This project is aimed at scintillator development for nuclear security applications and as such if successful will have broader impact on the society it serves in improving the possibilities for widespread deployment of sensitive radiation scanners. The interdisciplinary research on the intersection between organic/polymer chemistry and nuclear physics provides an ideal training ground for for all the graduate and undergraduate students involved. A hands-on curriculum for outreach activities on fluorescence and its applications will be developed and taught in local schools.
