Theoretical study of fusion reactions ^(32)S + ^(94,96)Zr and ^(40)Ca + ^(94,96)Zr and quadrupole deformation of ^(94)Zr  

作　　者：Bing Wang WeiJuan Zhao EnGuang Zhao ShanGui Zhou 

机构地区：[1]Department of Physics, Zhengzhou University [2]State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences [3]Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator

出　　处：《Science China(Physics,Mechanics & Astronomy)》2016年第4期58-65,共8页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Key Basic Research Program of China(Grant No.2013CB834400);the National Natural Science Foundation of China(Grant Nos.11175252;11120101005;11275248;11475115;and 11525524);the Knowledge Innovation Project of the Chinese Academy of Sciences(Grant No.KJCX2-EW-N01)

摘　　要：The dynamic coupling effects on fusion cross sections for reactions^(32)S + ^(94,96)Zr and ^(40)Ca + ^(94,96)Zr are studied with the universal fusion function formalism and an empirical coupled channel(ECC) model. An examination of the reduced fusion functions shows that the total effect of couplings to inelastic excitations and neutron transfer channels on fusion in ^(32)S +^(94)Zr(^(40)Ca +^(94)Zr) is almost the same as that in ^(32)S +^(96)Zr(^(40)Ca +^(96)Zr). The enhancements of the fusion cross section at sub-barrier energies due to inelastic channel coupling and neutron transfer channel coupling are evaluated separately by using the ECC model. The results show that effect of couplings to inelastic excitations channels in the reactions with94 Zr as target should be similar as that in the reactions with ^(96) Zr as target. This implies that the quadrupole deformation parameters β_2of ^(94)Zr and^(96) Zr should be similar to each other.However, β_2 's predicted from the finite-range droplet model, which are used in the ECC model, are quite different. Experiments on^(48) Ca +^(94)Zr or^(36) S +^(94)Zr are suggested to solve the puzzling issue concerning β_2for^(94)Zr.The dynamic coupling effects on fusion cross sections for reactions^（32）S ＋ ^（94,96）Zr and ^（40）Ca ＋ ^（94,96）Zr are studied with the universal fusion function formalism and an empirical coupled channel（ECC） model. An examination of the reduced fusion functions shows that the total effect of couplings to inelastic excitations and neutron transfer channels on fusion in ^（32）S ＋^（94）Zr（^（40）Ca ＋^（94）Zr） is almost the same as that in ^（32）S ＋^（96）Zr（^（40）Ca ＋^（96）Zr）. The enhancements of the fusion cross section at sub-barrier energies due to inelastic channel coupling and neutron transfer channel coupling are evaluated separately by using the ECC model. The results show that effect of couplings to inelastic excitations channels in the reactions with94 Zr as target should be similar as that in the reactions with ^（96） Zr as target. This implies that the quadrupole deformation parameters β_2of ^（94）Zr and^（96） Zr should be similar to each other.However, β_2 ＇s predicted from the finite-range droplet model, which are used in the ECC model, are quite different. Experiments on^（48） Ca ＋^（94）Zr or^（36） S ＋^（94）Zr are suggested to solve the puzzling issue concerning β_2for^（94）Zr.

关 键 词：empirical coupled channel model barrier distribution universal fusion function neutron transfer 

分 类 号：O571.44[理学—粒子物理与原子核物理] TG146.21[理学—物理]