Possible evidence for exchange effects in the /sup 16/O(/sup 6/Li,. cap alpha. )/sup 18/F reaction at E/sub /sup 6/Li/ = 34 MeV

Journal Article · Wed Sep 01 04:00:00 EDT 1976 · Phys. Rev., C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.14.977· OSTI ID:7175254

Moore, G E; Kemper, K W

Fifty-four-point angular distributions in the angular range 2.5/sup 0/ to 170/sup 0/ have been measured for the /sup 16/O(/sup 6/Li, ..cap alpha..)/sup 18/F reaction to the 1/sup +/ (0.0 MeV), 3/sup +/ (0.937 MeV), and 0/sup -/ + 5/sup +/ (1.1 MeV) states in /sup 18/F at a bombarding energy of 34 MeV. In addition, forward angle data have been measured for the 2/sup -/ (2.101 MeV), 1/sup +/ (3.725 MeV), 3/sup -/ (3.791 MeV), and 2/sup +/ (3.836 MeV) states. The angular distributions for all of the above states are forward peaked and have little structure at back angles. The general structure of the first 60/sup 0/ of the angular distributions can be reproduced by zero-range two-particle transfer distorted-wave Born-approximation calculations; however, the calculations are generally 3/sup 0/ and as much as 10degree out of phase with the data past the first maximum. A zero-range distorted-wave Born-approximation normalization factor of 100 is obtained assuming the 5/sup +/ state to be a pure (d/sub 5;2/)/sup 2/ configuration. Finite-range distorted-wave Born-approximation calculations which include the 2S and 1D components of /sup 6/Li do not improve the fits to the data and are similar to zero-range calculations at forward angles. The 1D component was shown to have little effect on the calculated angular distributions. The absolute magnitudes of the cross sections are predicted to within a factor of 2 when the /sup 18/F shell model wave functions of Kuo and Brown are used in the finite-range distorted-wave Born-approximation calculations. Two-particle and cluster form factors used in the finite-range calculations gave equivalent fits to the data. The magnitude of the cross section at angles greater than 90/sup 0/ and the phase of the forward angle data could not be reproduced by any of the calculations. The failure of the distorted-wave Born-approximation calculations at back angles suggests that a more complete description of the reaction mechanism which includes the exchange of an ..cap alpha.. particle in /sup 16/O with the /sup 6/Li projectile is necessary. (AIP)

• Research Organization: Physics Department, The Florida State University, Tallahassee, Florida 32306
• OSTI ID: 7175254
• Journal Information: Phys. Rev., C; (United States), Journal Name: Phys. Rev., C; (United States) Vol. 14:3; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

651325* -- Nuclear Properties & Reactions
A=6-19
Experimental-- Nuclear Reactions & Scattering-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALPHA SPECTRA
ANGULAR DISTRIBUTION
ANGULAR MOMENTUM
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BORN APPROXIMATION
CHARGED-PARTICLE REACTIONS
CROSS SECTIONS
DIRECT REACTIONS
DISTRIBUTION
DWBA
ENERGY LEVELS
ENERGY RANGE
EXCHANGE INTERACTIONS
FLUORINE 18
FLUORINE ISOTOPES
FUNCTIONS
HEAVY ION REACTIONS
HOURS LIVING RADIOISOTOPES
INTERACTIONS
ISOTOPES
LIGHT NUCLEI
LITHIUM 6 REACTIONS
MATHEMATICAL MODELS
MEV RANGE
MEV RANGE 10-100
MULTI-NUCLEON TRANSFER REACTIONS
NUCLEAR MODELS
NUCLEAR REACTIONS
NUCLEI
ODD-ODD NUCLEI
OXYGEN 16 TARGET
PARITY
PARTICLE PROPERTIES
RADIOISOTOPES
SHELL MODELS
SPECTRA
SPIN
STRIPPING
TARGETS
TRANSFER REACTIONS
TWO-NUCLEON TRANSFER REACTIONS
WAVE FUNCTIONS
ZERO-RANGE APPROXIMATION