2015/11/30 by L. -P. Euvé, F. Michel, R. Parentani +2 · 1 citation
Physics and Astronomy · #physics.flu-dyn #gr-qc
paper · pdf · doi:10.1103/physrevlett.117.121301
published as Phys. Rev. Lett. 117, 121301 (2016) · 11 pages, 14 figures. several points clarified; two new subsections in the Supplemental Material on the wave equation and the links with experiments in BECs
arxiv created 2016/07/29 · arxiv updated 2016/09/21
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 ≈ 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.