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arXiv · 1609.06273

Temperature dependence of the probability of "small heating" and spectrum of UCNs up-scattered on the surface of Fomblin oil Y-HVAC 18/8

V. V. Nesvizhevsky·A. Yu. Voronin·A. Lambrecht·S. Reynaud·E. V. Lychagin·A. Yu. Muzychka·G. V. Nekhaev·A. V. Strelkov
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Abstract

We performed precision measurements of the probability of small heating and spectrum of UCNs up-scattered on the surface of hydrogen-free oil Fomblin Y-HVAC 18/8 as a function of temperature. The probability is well reproducible, does not depend on sample thickness and does not evolve in time. It is equal (9.8+-0.2)10^(-6) at the ambient temperature. The spectrum coincides with those measured with solid-surface and nanoparticle samples. Indirect arguments indicate that spectrum shape weakly depends on temperature. Measured experimental data can be satisfactory described both within the model of near-surface nanodroplets and the model of capillary waves.

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V. V. Nesvizhevsky, A. Yu. Voronin, A. Lambrecht, S. Reynaud, E. V. Lychagin, A. Yu. Muzychka, G. V. Nekhaev, A. V. Strelkov. 2016-09-20. Temperature dependence of the probability of "small heating" and spectrum of UCNs up-scattered on the surface of Fomblin oil Y-HVAC 18/8. https://arxiv.org/abs/1609.06273

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