Effect of Shell Structure on Fission Isoscaling.pdf

Effect of Shell Structure on Fission Isoscaling M. Veselsky,1,2, ∗ G. A. Souliotis,2 and M. Jandel1 1Institute of Physics of the Slovak Academy of Sciences, Dubravska 9, Bratislava, Slovakia 2 Cyclotron Institute, Texas AM University, College Station, TX 77843 (Dated: February 8, 2008) Recently, the fragment yield ratios were investigated in the fission of 238,233U targets induced by 3 14 MeV neutrons [1]. The effect of the deformed shell structure around N=64 on the dynamics of 0 scission was suggested as an explanation of the observed breakdown of the isoscaling behavior. As 0 an alternative explanation, the effect of binding energy of final fragments, in particular the neutron 2 shell closure of the complementary fragment around N=82, was suggested by Friedman [2]. When c applying that concept consistently, the observed two breakdowns of the isoscaling behavior around e N=62 and N=80 signal the effect of two shell closures ( N=82 and N=64 ) on the dynamics of D scission. To separate the two effects, we examine the isoscaling plots obtained using fission fragment yield data from the spontaneous fission of the heavier nuclei 248,244Cm and find that the breakdown 2 of isoscaling around N=64 persists even if it can not be related to shell closure of the complementary 1 fragment and thus it manifests the effect of the deformed shell structure in the scission configuration. 1 v Isoscaling phenomena were observed in the isotopic compo