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arXiv · 1910.11937

Apparatus for in-beam hyperfine interactions and $g$-factor measurements: design and operation

A. E. Stuchbery·A. B. Harding·D. C. Weisser·N. R. Lobanov
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Abstract

The design and operation of apparatus for measurements of in-beam hyperfine interactions and nuclear excited-state $g$ factors is described. This apparatus enables a magnetic field of about 0.1 tesla to be applied to the target and the target temperature to be set between $\sim 4$ K and room temperature. Design concepts are developed mainly in terms of transient-field $g$-factor measurements following Coulomb excitation by the implantation perturbed angular correlation (IMPAC) technique. The formalism for perturbed angular correlations is outlined and a figure of merit for optimizing these measurements is derived to inform design. Particle detection is based on the use of silicon photodiodes of rectangular shape. The particle-$γ$ angular correlation formalism for this case is described. The experimental program to date includes temperature-dependent studies of hyperfine fields, transient-field $g$-factor measurements, and time-dependent perturbed angular distribution (TDPAD) studies.

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A. E. Stuchbery, A. B. Harding, D. C. Weisser, N. R. Lobanov. 2019-10-24. Apparatus for in-beam hyperfine interactions and $g$-factor measurements: design and operation. https://doi.org/10.1016/j.nima.2019.162985

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