Evidence for the stochastic aspect of promptγemission in spontaneous fission

Abstract

The prompt $\ensuremath{\gamma}$-ray energy and multiplicity distributions in the spontaneous fission of ${}^{252}$Cf have been measured using a highly segmented 4$\ensuremath{\pi}$ $\ensuremath{\gamma}$-ray calorimeter. Corrections were made for both distributions according to the detector response, which is simulated numerically using a model validated with the $\ensuremath{\gamma}$-ray calibration sources. A comparison of the total $\ensuremath{\gamma}$-ray energy distribution was made between the measurement and a simulation performed by random sampling of the corrected $\ensuremath{\gamma}$-ray energy and multiplicity distributions and then transporting those $\ensuremath{\gamma}$ rays through the response of the detector array. The agreement between the measurement and simulation for the mean energy and width is markedly improved at higher multiplicities compared to the lower ones, illustrating the diminishing correlation between the $\ensuremath{\gamma}$-ray and multiplicity energy and the stochastic aspect of the prompt $\ensuremath{\gamma}$ emission in spontaneous fission at higher multiplicities.