Comment on the transfer channel correction to the heavy ion subbarrier fusion cross section

Abstract

We examine the penetrability (or fusion cross section) in the influence of a favorable Q value transfer channel. We found that the formula for the cross section cannot be expressed as that given by Broglia et al. Our result does support their idea that the transfer channel gives rise to a large enhancement to the sub-Coulomb heavy ion fusion cross section.Recently, it has become clear that one-dimensional models cannot provide a satisfactory description for a heavy ion fusion cross section at subbarrier energies. ' This has led to the belief that the individual or the internal degrees of freedom of the colliding nuclei may play an important role in the fusion process. One of the interesting suggestions by Broglia et al. 3 is to explain the subbarrier fusion enhancement of the 'Ni+'Ni and 'Ni+'Ge systems by the coupling of nucleon transfer channels with favorable Q values. They are able to fit well the experimental fusion crosssection data by using the following formula:, ), (1) f(a, f ) =-)/2 1 1 . 1 1 r( -, + -,ia )r( -,+ -,a) r( g +ia)r( g + 2ib) 3 1 . 3 1 tion to be c, = [1v'f (et, e2)f (e2, et)] 'rt, c2= vf (et, e2) [1v f(at, e2) f(f2, et) ] = vf (e2, et) [Iv'f (et, e2)f (e2, «) ] 'r2, with v = (X/2) Jp, /0 and (6) where P(E) is the transfer probability and o t and o. 2 are the fusion cross sections for the entrance channel and the transferred channel, respectively.In this paper, we shall examine the validity of Eq. (1) in a quantum mechanical system. %e start with a simple model of a two channel Hamiltonian:

Effects of finite width of excited states on heavy-ion sub-barrier fusion reactions

“…A similar importance of the potential renormalisation concerning the effects of transfer reaction with positive Q-value on subbarrier fusion reactions has been pointed out in Ref. [28].…”

Near-barrier fusion ofS32+Zr90,96: The effect of multi-neutron

“…In addition to the fact that the questions of the possible occurrence of unexpected phenomena, such as breakup effects on the fusion reactions at near-barrier energies [5,6], are still unresolved, one has also to understand better the role of neutron transfers in the fusion processes [7,8]. For instance, effects of neutron-rich projectiles on the formation of superheavy elements (SHEs) [9,10], especially with the development of newly available radioactive ion beam (RIB) facilities, need to be clarified, as well as fusion hindrance at extremely low energies, which remains among the most interesting open questions in the nuclear astrophysics domain [11][12][13][14].…”

Sub-barrier fusion of 32S+90,96Zr: semi-classical coupled-channels approach

“…The heavy-ion fusion reactions in the low-energy range near and below the Coulomb barrier have been the subject of extensive experimental and theoretical efforts in the past decades [1][2][3]. Beside the fact that the questions of the possible occurence of unexpected phenomena, such as breakup effects on the fusion reactions at near barrier energies [3], are still unresolved, one has still to understand better the role of neutron transfers in the fusion process [4,5]. For instance, effects of neutron-rich projectiles on the formation of superheavy elements (SHE) [6], especially with the development of newly available Radioactive Ion Beams (RIB) facilities need to be clarified as well as fusion hindrance at extremely low energies that remain among the most interesting open questions in the nuclear astrophysics domain [7].…”