Scattering of co-current surface waves on an analogue black hole

TL;DR

This paper presents the first experimental observation of surface wave scattering on an analogue black hole horizon created by an accelerating flow, confirming hydrodynamical predictions of wave behavior in such effective spacetimes.

Contribution

It provides the first scattering experiment of surface waves on an analogue black hole horizon, validating hydrodynamical theory predictions in this context.

Findings

Measured scattering amplitudes match hydrodynamical theory

Partial scattering into counter-current waves observed

Supports the effective metric description of analogue horizons

Abstract

We report on what is to our knowledge the first scattering experiment of surface waves on an accelerating transcritical flow, which in the Analogue Gravity context is described by an effective spacetime with a black-hole horizon. This spacetime has been probed by an incident co-current wave, which partially scatters into an outgoing counter-current wave on each side of the horizon. The measured scattering amplitudes are compatible with the predictions of the hydrodynamical theory, where the kinematical description in terms of the effective metric is exact.