Does break-up affect 9Be + 209Bi fusion at the barrier?
C. Signorini1 - Z.H. Liu2,5 - Z.C. Li1,5 - K.E.G. Löbner3 - L. Müller1 - M. Ruan2 - K. Rudolph3 - F. Soramel4 - C. Zotti3 - A. Andrighetto1 - L. Stroe1 - A. Vitturi1 - H.Q. Zhang5
1 Physics Department of University and INFN, via Marzolo 8, I-35131 Padova, Italy
2 INFN, Legnaro National Laboratories, Legnaro, Padova, Italy
3 Sektion Physik, Ludwig-Maximilians-Universität München, D-85748 Garching, Germany
4 Physics Department of University and INFN, via delle Scienze 208, I-33100 Udine, Italy
5 China Institute of Atomic Energy, P.O.Box 275(10), Beijing 102413, P.R. of China
Received: 22 February 1999 / Revised version: 26 March 1999 Communicated by D. Schwalm
The 9Be + 209Bi fusion cross sections were measured in the 36.0 MeV Elab 50.0 MeV range, down to 0.6 mb, with high accuracy via in-beam detection of the ground state -decay of the evaporation residues produced. The elastic scattering cross sections around 150o and 135o were also obtained with moderate angular resolution. The cross sections below the barrier are reproduced by coupled channel calculations which include only one break-up channel with a moderate strength and a phenomenological renormalization of the potential depth. These simple calculations overestimate the cross sections above the barrier most likely due to the fact that the 9Be break-up process becomes much stronger. The barrier distributions extracted do not have evident break-up signature since they show one-barrier structure.
25.70.Jj Fusion and fusion fission reactions