Fission of Weakly Prolate 119Sn and Weakly Oblate ^(209)Bi Nuclei Induced by 500 and 672 MeV Negative Pions
作者机构:Physics DivisionPakistan Institute of Nuclear Science and Technology(PINSTECH)P.O.NiloreIslamabadPakistan
出 版 物:《Chinese Physics Letters》 (中国物理快报(英文版))
年 卷 期:2011年第28卷第9期
页 面:88-91页
核心收录:
学科分类:07[理学] 070202[理学-粒子物理与原子核物理] 0702[理学-物理学]
摘 要:Fission cross-sections of ^(119)Sn and ^(209)Bi induced by negative pions of two energies 500 and 672 MeV were measured using a CR−39 nuclear track ***-detector stacks were exposed to pion beams at the Brookhaven National Laboratory(USA).Measurement results are compared with the corresponding calculations using the computer code *** between measurements and calculations is fairly good for the ^(209)Bi target nuclei whereas it is poor for 119Sn at both investigated energies of 500 and 672 *** cross−section results of^( 119)Sn and ^(209)Bi are explained using the equilibrium properties of these nuclides including nuclear electric quadrupole moments which determine the shapes of nuclei.A logarithmic dependence of fission cross−section on Z^(2)/A is observed for the above−mentioned reactions and a critical limit of Z^(2)/A is identified with the value of 30 which divides the curve ofσf versus Z2/A into two regimes,one with weak dependence and the other with strong dependence.