Tensor polarized deuteron capture by [sup 3]He at and above the fusion resonance region
The absolute differential cross section and vector and tensor analyzing powers of the [sup 3]He([rvec d],[gamma])[sup 5]Li reaction have been measured at three energies: E[sub d](lab) = 8.6 MeV, E[sub d](lab) = 0.8 MeV where the beam was stopped in the target, and E[sub d](lab) = 0.6 MeV where the beam lost 0.3 MeV in the target. Additionally, absolute cross sections were measured at E[sub d](lab) = 0.8 MeV where the beam lost 0.4 MeV in the target, and E[sub d](lab) = 0.4 MeV where the beam was stopped in the target. Transition matrix element (TME) analyses of the observables at or below E[sub d](lab) = 0.8 MeV concluded that the reaction proceeds predominantly through s-wave (E1) capture, with small admixtures of M1 or E2 radiation. While multiple TME solutions exist, multichannel Resonating Group Model calculations performed at the peak of the fusion resonance at E[sub d](lab) = 0.45 MeV unambiguously select the solution with >89% [sup 4]s[sub 3/2](E1) TME strength as the physically preferred one. In the RGM picture, the strong capture cross section in the fusion resonance region is a consequence of the tensor force, which couples the [d+[sup 3]He][sup S=3/2][sub J=3/2] channel to the [p+[sup 4]He][sup S=1/2][sub J=3/2] channel in the scattering wave function, enabling the capture reaction to proceed via the [delta]S = 0 (E1) = 8.6 MeV, a transition matrix element fit indicates that the capture cross-section strength is dominated by s-wave E1 capture with an admixture of [approximately]20% d-wave E1 capture. In an RGM calculation at this energy, a non-zero tensor force is necessary to get agreement between data and theory for the relative strengths of the TME's. As with the E[sub d](lab) = 0.45 MeV calculation, the strong [sup 4]s[sub 3/2] (E1) capture strength is due to the coupling of the [d+[sup 3]He][sup S=3/2][sub J=3/2] scattering channel to the [p+[sup 4]He][sup S=1/2][sub J=3/2] scattering channel by the tensor force.
- Research Organization:
- Duke Univ., Durham, NC (United States)
- OSTI ID:
- 7112425
- Country of Publication:
- United States
- Language:
- English
Similar Records
Polarized d + sup 3 He capture into the 3/2 spl fusion resonance of sup 5 Li and the role of the tensor force
Observation of p-wave capture strength in the [sup 2]H([rvec d], [gamma]) [sup 4]He reaction at E[sub d] = 80-0 keV
Related Subjects
T-
& He-induced Reactions & Scattering-- (1992-)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALKALI METAL ISOTOPES
ALPHA DECAY RADIOISOTOPES
CALCULATION METHODS
CAPTURE
CHARGED PARTICLES
CHARGED-PARTICLE REACTIONS
CROSS SECTIONS
DEUTERONS
DIFFERENTIAL CROSS SECTIONS
E1-TRANSITIONS
ENERGY-LEVEL TRANSITIONS
HELIUM 3 REACTIONS
ISOTOPES
LIGHT NUCLEI
LITHIUM 5
LITHIUM ISOTOPES
MULTIPOLE TRANSITIONS
NUCLEAR REACTIONS
NUCLEI
ODD-EVEN NUCLEI
PARTIAL WAVES
RADIOISOTOPES
RESONATING-GROUP METHOD
S WAVES
SECONDS LIVING RADIOISOTOPES
VARIATIONAL METHODS