Abstract
The cumulative yields of various fission products within the 77–153 mass regions in the 2.5-GeV bremsstrahlung-induced fission of have been determined by using the recoil catcher and an off-line γ-ray spectrometric technique at the Pohang Accelerator Laboratory, Korea. The mass-yield distributions were obtained from the cumulative yields after charge-distribution corrections. The peak-to-valley () ratio, the average value of light mass () and heavy mass (), and the average postfission number of neutrons () were obtained from the mass yield of the reaction. The present and literature data in the reaction were compared with the similar data in the reaction at various excitation energies to examine the role of potential energy surface and the effect of standard I and standard II asymmetric modes of fission. It was found that (i) even at the bremsstrahlung end-point energy of 2.5 GeV, the mass-yield distribution in the reaction is triple humped, unlike reaction, where it is double humped. (ii) The peak-to-valley () ratio decreases with the increase of excitation energies. However, the ratio of the reaction is always lower than that of the reaction due to the presence of a third peak in the former. (iii) In both the and reactions, the nuclear structure effect almost vanishes at the bremsstrahlung end-point energies of 2.5–3.5 GeV.
2 More- Received 13 September 2017
- Revised 11 December 2017
DOI:https://doi.org/10.1103/PhysRevC.97.014614
©2018 American Physical Society