AbstractThe slowing-down times in water, toluene, and heavy water were obtained from measurements of capture-gamma-ray counting rates as a function of time after injection of a neutron burst. The times to the 1.46-eV resonance in indium were 0.75±0.5μsec, 1.5±0.3μsec, and 4.0±1.0μsec for the three moderators. The corresponding times to a 0.4-eV energy in cadmium were 1.75±0.5μsec, 3.25±0.3μsec, and 10.5±1.0μsec, respectively. Time-gated pulse-height spectra measurements in a large liquid scintillation detector were made to separate fast- from thermal-neutron interactions by taking advantage of slowing-down-time spectrometry. Steady-state pulse-height spectra measurements in water and in water plus indium illustrated the application of prompt-gamma-ray analysis to determination of capture rates.