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arXiv · 1303.5851

Temperature-dependent bulk viscosity of nitrogen gas determined from spontaneous Rayleigh-Brillouin scattering

Ziyu Gu·Wim Ubachs
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Abstract

Values for the bulk viscosity of molecular nitrogen gas (N2) were derived from spontaneous Rayleigh-Brillouin (RB) scattering at ultraviolet wavelengths (366.8 nm) and at a 90 degree scattering angle. Analysis of the scattering profiles yield values showing a linear increasing trend in the temperature interval from 255 K to 340 K. The present values, pertaining to hypersound acoustics at frequencies in the GHz domain, are found to be in agreement with results from acoustic attenuation experiments in N2 performed at MHz frequencies.

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Ziyu Gu, Wim Ubachs. 2013-03-23. Temperature-dependent bulk viscosity of nitrogen gas determined from spontaneous Rayleigh-Brillouin scattering. https://doi.org/10.1364/ol.38.001110

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