Study of complete and incomplete fusion in some heavy-ion induced reactions below 8 MeV/nucleon

Abstract

The study of heavy ion (HI) induced reaction dynamics at projectile energy below 8 MeV/nucleon has been topic of considerable interest for last few decades. In general, when two heavy ions are brought in contact, a variety of nuclear reactions may take place at energy near and/or above Coulomb barrier. The HI induced reactions provide a possibility of producing and studying the nuclei with high excitation energy and angular momentum. Enough evidences are available in literature to believe that complete fusion (CF) and incomplete fusion (ICF) are dominant mode of reaction at energy below 8 MeV/nucleon [1-6]. In complete fusion (CF) reaction, two nuclei interact at sufficient projectile energy (near and/or above the coulomb barrier) and at small values of the impact parameter, projectile amalgamates with the target nucleus leading to fully equilibrated compound nucleus (CN), in which all the angular momentum of the system is retained. In CF process, attractive nuclear potential overcomes the sum of repulsive coulomb and centrifugal potentials during projectile-target interaction. This implies the large transmission probability, even for partial waves (and#8804;), which involves all the nucleonic degrees-of-freedom of the projectile-target. For the entrance channel angular momentum carried by the system lying in the range 0and#8804;and#8804;, the probability of CF is supposed to be maximum. In CF process, total linear momentum carried by the projectile is given to composite system which recoils in the beam direction and traverse the larger range in the stopping medium. In this process, mass of the composite system is equal to mass of the projectile-target nucleus. At higher angular momentum of the projectile (gt) or relatively higher values of impact parameter, minimum mass overlap between projectile and target nuclei takes place, where incompletely fused composite system is formed as a result of partial linear momentum transfer from projectile to target O, nucleus. This is referred to ICF reaction mechanism.