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DOE OSTI · 2470154

High-throughput nuclear resonance time domain interferometry using annular slits

Pavlik, Marc·Brown, Dennis E.·Hu, Michael Y.·Zhao, Jiyong·Lurio, Laurence·Alp, E. Ercan
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Abstract

Nuclear resonance time domain interferometry (NR-TDI) is used to study the slow dynamics of liquids (that do not require Mössbauer isotopes) at atomic and molecular length scales. Here the TDI method of using a stationary two-line magnetized 57 Fe foil as a source and a stationary single-line stainless steel foil analyzer is employed. The new technique of adding an annular slit in front of a single silicon avalanche photodiode detector enables a wide range of momentum transfers (1 to 100 nm -1 by varying the distance between the annular slits and sample) with a high count rate of up to 160 Hz with a Δ q resolution of ±1.7 nm -1 at q = 14 nm -1 . The sensitivity of this method in determining relaxation times is quantified and discussed. The Kohlrausch–Williams–Watts (KWW) model was used to extract relaxation times for glycerol. These relaxation times give insight into the dynamics of the electron density fluctuations of glycerol as a function of temperature and momentum transfers.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSKohlrausch–Williams–Watts modelannular slitsmomentum transfersnuclear resonance time domain interferometryrelaxation times

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Pavlik, Marc, Brown, Dennis E., Hu, Michael Y., Zhao, Jiyong, Lurio, Laurence, Alp, E. Ercan. 2022-05-01. High-throughput nuclear resonance time domain interferometry using annular slits. https://doi.org/10.1107/s1600577522002843

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