Study on the Time Response of a Barium Fluoride Scintillation Detector for Fast Pulse Radiation Detection

Abstract

BaF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> crystal is well known for its short fluorescent decay time for its fast component. In measuring the time profile of y-ray flux density, it is important to suppress the contribution from the slow component in the BaF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> crystal. A multiple reflection and multiple-path (MRMP) short-wavelength pass filter is manufactured to achieve this goal, which can filter the slow component by wavelength selection. To accurately investigate the time profile of the fast component in the BaF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> crystal, <; 3 ps pulse length y-ray source is used. The experimental results show that this filter reduces the slow scintillation light emitted from the BaF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> crystal by 99.7% with a detection efficiency of ≈0.11 electrons/γ for the fast component. The rise time, full-width at half-maximum (FWHM), and duration time for the fast component in a BaF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> detector are 0.31, 1.12, and 2.92 ns, respectively. The fast fluorescent component of the BaF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> crystal is short enough for subnanosecond pulse radiation detection.