[2A05-09] Nuclear Data Measurement 2

[2A08] A systematic measurement of mass-centroids for light/heavy fragments in actinide fission

*Kentaro Hirose¹, Katsuhisa Nishio¹, Leguillon Romain¹, Mark Vermeulen¹, Kean Kun Ratha^2,1, Hiroyuki Makii¹, Riccardo Orlandi¹, Kazuaki Tsukada¹, Masato Asai¹, Tetsuya K Sato¹ (1. Japan Atomic Energy Agency, 2. Tokyo Tech)

Keywords:fission, fission fragment mass distribution, multinucleon transfer reaction

We have measured fission-fragment mass distributions for totally 52 nuclides from Th to Cf by multi-nucleon transfer reactions using O18 beam and actinide targets of Th232, U238, Np237, Am243 and Cm248 at the Tokai tandem accelerator facility of Japan Atomic Energy Agency. Compound nuclei were determined by the particle identification of the ejectiles using a silicon DE-E telescope. Two fission fragments were detected in coincidence using 4 multi-wire proportional counters. Their masses were deduced from their flight-time difference. It is found that the asymmetric fission is dominant in the excitation energy region from 10 to 20MeV. In order to deduce the mass-centroids for the light/heavy fragments, a Gaussian fitting with two component (asymmetric and symmetric modes) was applied to the measured fission fragment mass distributions. In this presentation, a comparison of the present data with the existing data and their systematics will be discussed.