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Updated: Jun 28, 2026

Hyperpolarized Xenon for NMR and MRI Applications
Published on: September 6, 2012
Hyperfine suppression of 2 3 S 1--3 3 P J transitions in 3He
I A Sulai1, Qixue Wu, M Bishof
1Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA.
Abstract:
Two anomalously weak transitions within the 2(3)S_(1)--3(3)P_(J) manifolds in 3He have been identified. Their transition strengths are measured to be 1000 times weaker than that of the strongest transition in the same group. This dramatic suppression of transition strengths is due to the dominance of the hyperfine interaction over the fine-structure interaction. An alternative selection rule based on IS coupling (where the nuclear spin is first coupled to the total electron spin) is proposed. This provides qualitative understanding of the transition strengths. It is shown that the small deviations from the IS coupling model are fully accounted for by an exact diagonalization of the strongly interacting states.
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