https://doi.org/10.1140/epja/i2013-13063-2
Regular Article - Experimental Physics
Fusion of 60Ni + 100Mo near and below the Coulomb barrier
Multi-phonon and transfer couplings down to the hindrance region
19893
Laboratori Nazionali di Legnaro, INFN, I-35020, Legnaro (Padova), Italy
29893
Dipartimento di Fisica e Astronomia, Università di Padova, and INFN, Sezione di Padova, I-35131, Padova, Italy
39893
Physics Division, Argonne National Laboratory, 9700 S. Cass Avenue, 60439, Argonne, IL, USA
49893
Department of Physics and Astronomy, Louisiana State University, 70803, Baton Rouge, LA, USA
59893
University of Notre Dame, 46556, Notre Dame, IN, USA
69893
Fermi National Accelerator Laboratory, 60510, Batavia, IL, USA
79893
Lawrence Livermore National Laboratory, 94550, Livemore, CA, USA
89893
University of Chicago, 60637, Chicago, IL, USA
* e-mail: stefanini@lnl.infn.it
Received:
23
April
2013
Revised:
3
May
2013
Accepted:
10
May
2013
Published online:
27
May
2013
The fusion excitation function of 60 Ni + 100 Mo has been measured from above the Coulomb barrier down to a cross section around 2 μb, looking for coupling and hindrance effects in this soft medium-mass system with positive Q-values for several neutron transfer channels. A comparison is made with previous results for 64 Ni + 100 Mo where no Q > 0 transfer channels exist and the hindrance effect is quite clear. The two excitation functions are very similar, as well as the corresponding logarithmic derivatives showing analogous saturations below the barrier. It appears that transfer couplings to Q > 0 channels seem to play a marginal role near and below the barrier for 60 Ni + 100 Mo , even if measurements of cross sections lower than 1 μb would be needed also for this system. Coupled-channels calculations confirm these observations and indicate that multi-phonon excitations dominate the fusion dynamics in the whole measured energy range.
© SIF, Springer-Verlag Berlin Heidelberg, 2013