Speaker
Felix Liang
(Oak Ridge National Laboratory)
Description
Neutron-rich fission fragments accelerated to energies around the Coulomb
barrier are used for studying the reaction mechanisms of fusion at HRIBF.
Fusion excitation functions have been measured using neutron-rich radioactive
132Sn beams incident on Ca and Ni targets. Large sub-barrier fusion
enhancement has been observed in the reaction with the 40Ca target.
A previously measured fusion excitation function for 40Ca+124Sn
suggests that the enhancement is due to
multineutron transfer. The Q-values for multineutron transfer in
the reaction of 132Sn with 58Ni are comparable to those in the
reactions with 40Ca, but the sub-barrier fusion enhancement is
significantly smaller. Furthermore, it is a surprise to find that the
sub-barrier fusion enhancement for 118Sn+64Ni, which has no positive
Q-value for neutron transfer, is comparable to that for 132Sn+58Ni.
To investigate the differences in the correlations between transfer and
sub-barrier fusion enhancement for Sn+Ca and Sn+Ni systems, the fusion
excitation functions for 124Sn+46,50Ti have been measured. The
neutrons transferred from 124Sn to 46Ti populate similar orbitals as those in
132Sn+40Ca but different from those in 132Sn+58Ni. A
comparison of the fusion excitation functions for Sn+Ca, Sn+Ti, and Sn+Ni will
be presented. Coupled-channels calculations to analyze the contributions of
coupling to transfer will be discussed.
*This research was supported by the US Department of Energy Office of Nuclear Physics.
Primary author
Felix Liang
(Oak Ridge National Laboratory)
Co-authors
Dr
Anne Caraley
(SUNY at Oswego)
Dr
Carl Gross
(Oak Ridge National Laboratory)
Dr
Dan Shapira
(Oak Ridge National Laboratory)
Dr
Karin Lagergren
(Oak Ridge National Laboratory)
Dr
Mitch Allmond
(Oak Ridge National Laboratory)
Dr
Paul Mueller
(Oak Ridge National Laboratory)
Dr
Robert Varner
(Oak Ridge National Laboratory)
Dr
Zach Kohley
(Oak Ridge National Laboratory)
