Reactions between medium-mass nuclei at subbarrier energies

Conference · Thu Nov 01 04:00:00 EST 1990

OSTI ID:6172334

Kim, H J

A number of diverse theories can account, to a similar extent, for experimentally observed large enhancements in subbarrier fusion cross sections. For example, coupled-channels, neck-formation, distributed-barrier, and direct absorption theories have been used with comparable degrees of success to analyze the enhancement in {sup 58}Ni + {sup 58}Ni fusion cross sections at subbarrier energies. This example illustrates that, although necessary, fusion cross sections alone are not sufficient to assess what really is the underlying enhancement mechanism. Although their details vary, these theories share a reliance on interactions between the incident and one or more outgoing reaction channels to produce the enhancement. Being microscopic, the coupled-channels approach requires interactions with specific individual exit channels, such as inelastic and nucleon transfer. On the other hand, being macroscopic in nature, the neck-formation and distributed-barrier theories treat the interactions in a more global way. Thus, in addition to fusion, detailed studies of exit channels in general at subbarrier energies are very much needed in order to develop a good theoretical understanding of how the enhancement really comes about. We present results from our study of transfer reactions between {sup 50}Ti and {sup 93}Nb that pertain to the subbarrier neck. Since the experimental arrangement used is the same as that of our previous study, only a brief description is given. Target and target-like ejectiles emitted forward from the bombardment of thin {sup 50}Ti targets by {sup 93}Nb beams were first magnetically analyzed and then detected by a hybrid position-sensitive gas detector system, which was placed at the nominal focal plane of the magent; ejectiles emitted at 10{degree} {le} {theta} {le} 20{degree} angular range were investigated at bombarding energies of 283.1, 291.2, 273.2, 302.0, and 306.9 MeV.

• Research Organization: Oak Ridge National Lab., TN (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6172334
• Report Number(s): CONF-9009311-1; ON: DE91005012
• Country of Publication: United States
• Language: English

Related Subjects

651520* -- Nuclear Properties & Reactions
A=39-58
Experimental
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BARYONS
CHARGED-PARTICLE REACTIONS
CHROMIUM ISOTOPES
COUPLED CHANNEL THEORY
CROSS SECTIONS
DIRECT REACTIONS
ELEMENTARY PARTICLES
ENERGY SPECTRA
FERMIONS
HADRONS
HEAVY ION FUSION REACTIONS
HEAVY ION REACTIONS
ISOTOPES
NIOBIUM 93 REACTIONS
NUCLEAR REACTIONS
NUCLEONS
SPECTRA
TARGETS
TITANIUM 50 TARGET
TRANSFER REACTIONS
VANADIUM ISOTOPES