Deuterated-xylene (xylene-d 10 ; EJ301D): A new, improved deuterated liquid scintillator for neutron energy measurements without time-of-flight
In conjunction with Eljen Technology, Inc. (Sweetwater,TX) we have designed, constructed, and evaluated a 3 in. x 3 in. deuterated-xylene organic liquid scintillator (C 8 D 10 ; EJ301D) as a fast neutron detector. Similar to deuterated benzene (C 6 D 6 ; NE230, BC537, and E1315) this scintillator can provide good pulse shape discrimination between neutrons and gamma rays, has good timing characteristics, and can provide a light spectrum with peaks corresponding to discrete neutron energy groups up to ca. 20 MeV. Unlike benzene -based detectors, deuterated xylene is less volatile, less toxic, is not known to be carcinogenic, has a higher flashpoint, and hence is much safer for many applications. In addition E1301D can provide slightly more light output and better PSD than deuterated-benzene scintillators. We show that, as with deuterated-benzene scintillators, the light -response spectra can be unfolded to provide useable neutron energy spectra without need for time-of-flight (ToF). An array of these detectors arranged at many angles close to a reaction target can be much more effective ( x 10 to x 100 or more) than an array of long-path ToF detectors which must utilize a narrowly-bunched and pulse-selected beam. Here, as we demonstrate using a small Van de Graaff accelerator, measurements can thus be performed when a bunched and pulse -selected beam (as needed for time-of-flight) is not available.