Influence of projectile breakup on complete fusion

A MUKHERJEE^* and M K PRADHAN

Saha Institute of Nuclear Physics, 1/AF, Bidhan Nagar, Kolkata 700 064, India

^*Corresponding author. E-mail: anjali.mukherjee@saha.ac.in

Abstract. Complete fusion excitation functions for

$^{11,10}$B\,+\,$^{159}$Tb and $^{6,7}$Li\,+\,$^{159}$Tb have been

reported at energies around the respective Coulomb barriers. The

measurements show significant suppression of complete fusion

cross-sections at energies above the barrier for $^{10}$B\,+\,$^{159}$Tb

and $^{6,7}$Li\,+\,$^{159}$Tb reactions, when compared to those for

$^{11}$B\,+\,$^{159}$Tb. The comparison shows that the extent of

suppression of complete fusion cross-sections is correlated with the

$\alpha$-separation energies of the projectiles. Also, the measured

incomplete fusion cross-sections show that the $\alpha$-particle

emanating channel is the favoured incomplete fusion process.

Inclusive measurement of the $\alpha$-particles produced in

$^{6}$Li\,+\,$^{159}$Tb reaction has been carried out. Preliminary CDCC

calculations carried out to estimate the $\alpha$-yield following

$^{6}$Li breaking up into $\alpha$\,+\,$d$ fail to explain the measured

$\alpha$-yield. Transfer processes seem to be important contributors.

Keywords. Weakly bound nuclei; fusion, breakup.

PACS Nos 25.70.Jj; 25.70.Pj; 25.70.Mn; 25.70.+q