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arXiv · 1511.08145

Observation of noise correlated by the Hawking effect in a water tank

L. -P. Euvé·F. Michel·R. Parentani·T. G. Philbin·G. Rousseaux
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Abstract

We measured the power spectrum and two-point correlation function for the randomly fluctuating free surface on the downstream side of a stationary flow with a maximum Froude number $F_{\rm max} \approx 0.85$ reached above a localised obstacle. On such a flow the scattering of incident long wavelength modes is analogous to that responsible for black hole radiation (the Hawking effect). Our measurements of the noise show a clear correlation between pairs of modes of opposite energies. We also measure the scattering coefficients by applying the same analysis of correlations to waves produced by a wave maker.

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L. -P. Euvé, F. Michel, R. Parentani, T. G. Philbin, G. Rousseaux. 2016-07-29. Observation of noise correlated by the Hawking effect in a water tank. https://doi.org/10.1103/physrevlett.117.121301

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