Fusion excitation functions have been measured for the first time with rather good accuracy for 32 S + 90 Zr and 32 S + 96 Zr near and below the Coulomb barrier. The sub-barrier cross sections for 32 S + 96 Zr are much larger than for 32 S + 90 Zr. A coupled-channels calculation considering the inelastic excitations is capable of describing sub-barrier enhancement only for 32 S + 90 Zr. The unexplained part for 32 S + 96 Zr is found to be correlated with the positive-Q-value intermediate neutron transfers in this system. The comparison with 40 Ca + 96 Zr suggests that couplings to the positive-Q-value neutron transfer channels may play a role in the sub-barrier fusion enhancement. Multi-neutron transfers are taken into account in Zagrebaev's semiclassical model to explain the discrepancies of the sub-barrier fusion cross sections for 32 S + 96 Zr.

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The angular distributions of fission fragments for the 32 S+ 184 W reaction at center-of-mass energies of 118. 8, 123.1, 127.3, 131.5, 135.8, 141.1 and 144.4 MeV were measured. The experimental fission excitation function is obtained. The fragment angular anisotropy (A exp ) is found by extrapolating the each fission angular distributions. The measured fission cross sections of the 32 S+ 182,184 W reaction are decomposed into fusion-fission, quasifission and fast fission contributions by the dinuclear system model. The total evaporation residue excitation function for the 32 S+ 184 W reaction calculated in the framework of the advanced statistical model is in good agreement with the available experimental data up to about E c.m. ≈ 160 MeV. The theoretical descriptions of the experimental capture excitation functions for both reactions and quantities K 2 0 , < ℓ 2 > and A exp which characterize angular distributions of the fission products were performed by the same partial capture cross sections at the considered range of beam energy.

The fusion excitation functions have been measured with rather good accuracy for 32 S+ 90 Zr and 32 S+ 96 Zr near and below the Coulomb barrier. The sub-barrier cross sections for 32 S+ 96 Zr are much larger compared with 32 S+ 90 Zr. Semi-classical coupled-channels calculations including two-phonon excitations are capable to describe sub-barrier enhancement only for 32 S+ 90 Zr. The remaining disagreement for 32 S+ 96 Zr comes from the positive Q-value intermediate neutron transfers in this system. The comparison with 40 Ca+ 96 Zr suggests that couplings to the positive Q-value neutron transfer channels may play a role in the sub-barrier fusion enhancement. A rather simple model calculation taking neutron transfers into account is proposed to overcome the discrepancies of 32 S+ 96 Zr.

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