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Publication Citation: Comment on "Enhanced polarization and mechanisms in optically pumped hyperpolarized 3He in the presence of 4He"

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Author(s): Thomas R. Gentile; M E. Hayden; P.J. Nacher; A K. Petukhov; B Saam; T G. Walker;
Title: Comment on "Enhanced polarization and mechanisms in optically pumped hyperpolarized 3He in the presence of 4He"
Published: July 24, 2013
Abstract: H.H. Chen et al [1] claim that adding 4He to spin-exchange optical pumping (SEOP) cells confines 3He atoms to a diffusion-limited region, which effectively reduces the wall relaxation factor X. Here X is a phenomenological parameter used to characterize typical SEOP cells; it quantifies the observation that the measured linear slope of the relaxation rate with alkali density exceeds the spin-exchange rate. In addition they claim to demonstrate that magnetic field gradients cause a diffusive motion of 3He. We argue that these claims and other central conclusions drawn by the the authors of [1] are unjustified and/or unphysical. We also draw attention to several additional issues and shortcomings associated with the results, analysis, and presentation of data in [1] that confound clear interpretation."
Citation: Physical Review A
Pages: pp. 017401-1 - 017401-3
Keywords: He3; He4; spin-exchange optical pumping;
Research Areas: Radiation Physics, Neutron Research