LI-6(N,ALPHA)T CROSS-SECTION FROM 70-KEV TO 3000-KEV FROM THE U-235(N,F) CALIBRATION OF A THIN GLASS SCINTILLATOR

The efficiency of a 0. 5-mm-thick **6Li glass scintillation monitor was determined above the ″1/v″ region by comparison with the counting rate of a ten-plate **2**3**5U fission ionization chamber in a neutron beam from the Oak Ridge Electron Linear Accelerator. The chief difference in derived **6Li(n, varies directly as ) cross sections from the ENDF/B-V evaluation is a slightly greater width ( similar 8%) of the prominent resonance peaking near 240 keV and a higher cross section in the wings. The steep rise in efficiency from 3500 to 5000 keV is attributed primarily to the **1**6O(n, varies directly as ) reaction.