Experimental search for nonfusion yield in the heavy residues emitted in the 11B+12C reaction.

Abstract

The mechanism responsible for fusion cross section limitations in light heavy-ion systems has been the focus of numerous experimental and theoretical studies. Many of the experimental investigations have involved a study of the heavy residues emitted following the interaction of light heavy ions. One difficulty encountered in such studies is separating events from competing reaction mechanisms, such as direct transfer and incomplete fusion, from fusion-evaporation events. In the present work, direct and reverse reaction kinematics are exploited in an effort to determine the magnitude of the nonfusion strength in the heavy residue spectra for the interaction of /sup 11/B and /sup 12/C. It is particularly important that the /sup 11/B+ /sup 12/C fusion strength be properly identified, as it is the measured fusion strength in this entrance channel which in earlier studies clearly ruled out a fusion cross section limitation based upon having reached a critical density of compound nuclear states. In agreement with the earlier investigations, the present study reveals no significant nonfusion component in the heavy residue spectra for the /sup 11/B+ /sup 12/C reaction.