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A new nanoparticle loaded plastic scintillator embedded in a glass substrate detects and discriminates all species of
radiation emitted from fissionable bomb making materials. The fast electron scintillating resin is doped with tailored
charge conversion nanoparticles to produce characteristic optical pulses. The created optical pulses exit the detector,
since the nanoparticles are appreciably smaller than the wavelength of light. Microsandblasting is used to etch deep
cavities in the glass substrate forming independent optical paths. The doped resin is injected into the cavities and cured.
A separate off-the-shelf PM tube linearly amplifies the created light pulse into a usable electrical signal. By using
tailored nanoparticles, the physical mechanisms for converting different species of radiation into lower energy electrons
allows for pulse height spectroscopy to discriminate between alpha, beta, gamma, and neutron radiation. A 90Sr source
was used to test the beta detector, which is loaded with W. The drop in count rates versus distance was found to be
similar to traditional detectors. The gamma detector loaded with Pb nanoparticles was tested with a 60Co source. The
addition of Pb provided greater sensitivity to the gamma radiation. A 210Pl source was used to test the glass doped
scintillator. The count rates remained fairly constant for varying distances since alpha particles tend to travel in straight
paths until losing most of their initial energy. The 157Gd loaded scintillator was tested with an Am/Be source. 157Gd has
the largest thermal neutron absorption cross section at 255,000 barns and releases a usable characteristic 72keV electron
in 39% of the capture reactions.
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