Angular anisotropy in the /sup 6/Li(n,. cap alpha. )/sup 3/H reaction below 100 keV

Conference · Sat Oct 01 04:00:00 EDT 1977 · Natl. Bur. Stand. (U.S.), Spec. Publ.; (United States)

OSTI ID:5200145

Harvey, J A ^[1]; Schroeder, I G

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1. Oak Ridge National Lab., TN

The data on the differential (n,..cap alpha..) cross section of /sup 6/Li are reviewed below a neutron energy of 100 keV. Measurements in this region, in contrast to that above 100 keV, have been few. Only recently has interest increased as large and unsuspected anisotropies have been observed in this energy region. Thu, at 25 keV an anisotropy amounting to 67 percent in the forward-to-backward direction has been observed; while in the region between 1 eV and 10 keV measurements indicate that in the forward-to-backward 66/sup 0/ cone the asymmetry has an energy dependence, in the laboratory system, which can be expressed analytically as 1 + 0.0055 ..sqrt..E/sub n/(eV). These angular anisotropies seem to arise from interference between the large p-wave resonance at 247 keV and many s-wave resonances which account for the large 1/v (n,..cap alpha..) thermal cross section. New and detailed measurements of the differential (n,..cap alpha..) cross section are needed, not only to be able to account analytically for these interference effects, but also because it is necessary to consider these anisotropies when the /sup 6/Li(n,..cap alpha..)/sup 3/H cross section is used as a standard. 6 figures, 1 table.

• OSTI ID: 5200145
• Conference Information: Journal Name: Natl. Bur. Stand. (U.S.), Spec. Publ.; (United States) Journal Volume: 493
• 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 PARTICLES
ANGULAR DISTRIBUTION
ANISOTROPY
BARYON REACTIONS
BARYONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHARGED PARTICLES
COMPOUND-NUCLEUS REACTIONS
CROSS SECTIONS
DIFFERENTIAL CROSS SECTIONS
DISTRIBUTION
ELEMENTARY PARTICLES
ENERGY RANGE
EV RANGE
FERMIONS
HADRON REACTIONS
HADRONS
HYDROGEN ISOTOPES
INTERFERENCE
INTERMEDIATE NEUTRONS
ISOTOPES
KEV RANGE
KEV RANGE 10-100
LIGHT NUCLEI
LITHIUM 6 TARGET
NEUTRON REACTIONS
NEUTRONS
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
NUCLEONS
ODD-EVEN NUCLEI
RADIOISOTOPES
RESONANCE
TARGETS
TRITIUM
YEARS LIVING RADIOISOTOPES