Mogens T. Levinsen

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When a container of fluid is oscillated vertically, capillary waves develop on the surface if the amplitude exceeds a critical value. Experimentally one finds that the motion of small particles on the surface of the fluid is close to Brownian. Here we study the relative motion of particle pairs. The experiment establishes that particle motion is strongly(More)
We examine particle trajectories in capillary waves formed on a water surface subject to vertical vibrations. We focus on the role of a distinct length scale present in our experiment, namely, the wavelength l of the surface waves. We observe non-Brownian particle trajectories with a fractal dimension D different from the random walk value D ෇ 2. A(More)
The size of the light-emitting region is a key parameter toward understanding the light-emitting processes in a sonoluminescing bubble. Here we present measurements of interference effects from particles with a diameter of approximately 2 microm situated 6-10 microm from a sonoluminescing bubble. From the angular size of the pattern and from an estimated(More)
Excitation of shape instabilities represents one route to bubble death in single-bubble sonoluminescence. This feature is satisfactorily explained by an expansion to first order in the amplitude of a shape distortion in the form of a spherical harmonic. By taking the expansion to second order, it is found that regions of parameter space exist where the(More)
A long-standing issue in the field of long-time-stable, water-based, single-bubble sonoluminescence has been the close similarity of the spectra to that of blackbody radiation, the question being whether the similarity is just a weird coincidence, with the bubbles being, on the whole, transparent to their own radiation. One mechanism that has been suggested(More)
We report the existence of a second type of recycling mode that occurs for air-seeded bubbles. Observation of period doubling in both the stable, the first type, and the second type of recycling mode, together with simultaneous measurement of the relative phase of light emission compared to the drive, shows that the instability boundaries of period doubling(More)
In the early days of stable single-bubble sonoluminescence, it was strongly debated whether the emission was blackbody radiation or whether the bubble was transparent to its own radiation (volume emission). Presently, the volume emission picture is nearly universally accepted. We present new measurements of spectra with apparent color temperatures ranging(More)
We present observations of stable spherical symmetry broken states in single bubble sonoluminescence including observations of period doubled states. States observed involve both spatially oriented states and states with a tumbling symmetry axis. The observations are made using a fiber based four-channel correlation scheme. The measurements are made both(More)
In a thought-provoking paper, Couder and Fort [Phys. Rev. Lett. 97, 154101 (2006)] describe a version of the famous double-slit experiment performed with droplets bouncing on a vertically vibrated fluid surface. In the experiment, an interference pattern in the single-particle statistics is found even though it is possible to determine unambiguously which(More)
We present experimental spectra of single sonoluminescing bubble in water at different dissolved argon concentrations and excitation levels. All the relevant experimental conditions are either measured directly or derived from measured quantities for each spectrum, thus the parametric dependence of the spectra can be analyzed. To characterize the data in a(More)