Measurement of ⁷Li(n,γ0)⁸Li cross sections at En=1.5-1340 eV

J. C. Blackmon, Oak Ridge National Laboratory
A. E. Champagne, The University of North Carolina at Chapel Hill
J. K. Dickens, Oak Ridge National Laboratory
J. A. Harvey, Oak Ridge National Laboratory
M. A. Hofstee, The University of North Carolina at Chapel Hill
S. Kopecky, Universitat Wien
D. C. Larson, Oak Ridge National Laboratory
D. C. Powell, The University of North Carolina at Chapel Hill
S. Raman, Oak Ridge National Laboratory
M. S. Smith, Oak Ridge National Laboratory

Abstract

The 7Li(n,γ)8Li cross section is important in inhomogeneous big bang models, and as a constraint on model parameters used to determine the solar 7Be(p,γ)8B reaction rate. Values of the 7Li(n,γ0)8Li reaction cross section were measured for neutron energies between 1.5 and 1340 eV at the Oak Ridge Electron Linear Accelerator. The normalization of the cross section was determined by measuring the gamma-ray yield from the 7Li(n,γ0)8Li reaction relative to that from the 10B(n,αγ)7Li reaction. The cross section was found to have the inverse neutron-velocity relationship (1/υ) indicative of s-wave capture. These results help resolve ambiguities in previous measurements.