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Resolving the space-time structure of sonoluminescence by intensity interferometry  [PDF]
Claus Slotta,Ulrich Heinz
Physics , 1997, DOI: 10.1103/PhysRevE.58.526
Abstract: We analyze the spatial and temporal resolving power of two-photon intensity interferometry for the light emitting source in single bubble sonoluminescence (SBSL). We show that bubble sizes between several 10 nm and 3 um can be resolved by measuring the transverse correlation function, but that a direct determination of the flash duration via the longitudinal correlation function works only for SBSL pulses which are shorter than 0.1 ps. Larger pulse lengths can be determined indirectly from the intercept of the angular correlator at equal photon frequencies. The dynamics of the bubble is not accessible by two-photon interferometry.
Single Bubble SonoLuminescence of Particles model  [PDF]
Mahamadou Adama Maiga
Physics , 2012,
Abstract: The Single Bubble SonoLuminescence is a phenomenon where the vapor bubble trapped in a liquid collapse by emitting of a light. It is very known that the temperature inside the bubble depends on the radius, during the collapse, the temperature can reach thousands of Kelvins and that the light would be emitted by radiation of the ionized gas inside the bubble. So, studies show that in certain cases neither an imploding shock nor a plasma has been observed and the temperature is not high enough to explain the spectrum observed. The Single Bubble SonoLuminescence remains a subject of study. For this study we consider the bubble as a box where the free particles (particularly electrons) stemming from the molecules dissociation, are are trapped and confined within the bubble. The confinement allows the particles to acquire some energy during the collapse which they lose in the form of light and also to be considered to bind to the bubble as an electron is bound to the nucleus in an atom. So, with regard to the bubble the energy of the particles can be considered to quantify, and with the quantum theory, by putting some hypotheses, their energy is determined well. The energy is physically acceptable that if the bubble is spherical. This necessary condition of a spherical bubble of the model is observed experimentally in the collapse phase but not in the afterbounce phase of the bubble, explain why the bubble emits of light in the collapse but not in the phase of the afterbounces where she can be smaller, and constitute a validation of the Single Bubble SonoLuminescence of particles model. For the application of the Single Bubble SonoLuminescence of particles model we consider a electron free particle of mass . We note that the interval of time between and energy (who can be considered as the duration when the bubble emits some light) is of the order of picoseconds, the same order that the shortest pulses observed experimentally.
Bubble Shape Oscillations and the Onset of Sonoluminescence  [PDF]
Michael P. Brenner,Detlef Lohse,T. F. Dupont
Physics , 1995, DOI: 10.1103/PhysRevLett.75.954
Abstract: An air bubble trapped in water by an oscillating acoustic field undergoes either radial or nonspherical pulsations depending on the strength of the forcing pressure. Two different instability mechanisms (the Rayleigh--Taylor instability and parametric instability) cause deviations from sphericity. Distinguishing these mechanisms allows explanation of many features of recent experiments on sonoluminescence, and suggests methods for finding sonoluminescence in different parameter regimes.
Study of the moving single bubble sonoluminescence  [cached]
M. AliAsgarian,S. Z. Kalantari
Iranian Journal of Physics Research , 2008,
Abstract: Moving single bubble sonoluminescence has been discovered after searches to find the fluids other than water for observing SBSL. The main property of these fluids is their more viscosity rather than water. In this paper, after introducing the forces which act on sonoluminescing bubble, the moving of the bubble have been simulated. For this purpose, the bubble’s equation of motion is coupled with the Rayleigh-Plesset and temperature equations. For solving these equations we have used the Runge-Kutta method. We have shown that the path of the bubble is the same as an ellipsoidal movement near the center of the flask. One of the main results of this simulation is that the maximum temperature (at collapse moment) of the bubble is increased by reducing the distance of the bubble from the center of flask. Due to direct relation between light emission and the temperature of the bubble, the same result can be get for intensity of the light. In other words, we have shown that the intensity of the emitted light from bubble oscillates. Accordingly we propose that the measurement of the light oscillation from the moving bubble is as a criterion for experiment on moving single bubble sonoluminescence.
Novel Mechanism for Single Bubble Sonoluminescence  [PDF]
B. P. Lavrov
Physics , 2001,
Abstract: Careful re-examination of typical experimental data made it possible to show that the UV continua observed in multi-bubble (MBSL) and single-bubble (SBSL) sonoluminescence spectra have the same physical nature - radiative dissociation of electronically excited hydrogen molecules [and probably hydrides of heavy rare gases like ArH*] due to spontaneous transitions between bound and repulsive electronic states. The proposed mechanism is able to explain all available spectroscopic observations without any exotic hypothesis but in terms usual for plasma spectroscopy.
HBT interferometry: historical perspective
Padula, Sandra S.;
Brazilian Journal of Physics , 2005, DOI: 10.1590/S0103-97332005000100005
Abstract: i review the history of hbt interferometry, since its discovery in the mid 1950's, up to the recent developments and results from bnl/rhic experiments. i focus the discussion on the contributions to the subject given by members of our brazilian group.
HBT Interferometry: Historical Perspective  [PDF]
Sandra S. Padula
Physics , 2004, DOI: 10.1590/S0103-97332005000100005
Abstract: I review the history of HBT interferometry, since its discovery in the mid 1950's, up to the recent developments and results from BNL/RHIC experiments. I focus the discussion on the contributions to the subject given by members of our Brazilian group.
Finite-amplitude vibration of a bubble and sonoluminescence
Qian Zu-Wen,Xiao Ling,Guo Liang-Hao,

中国物理 B , 2004,
Abstract: Numerical solutions of the differential equation for a bubble performing finite-amplitude vibration are given in detail for a variety of situations. The results demonstrate that in lower acoustic pressure (maximum Mach number very low) its vibration has bounce. When acoustic pressure is in excess of 1.18atm and the instantaneous radius of the bubble approaches its equivalent Van der Waals radius, the maximum velocity and acceleration on the surface of a bubble have a huge increase in a very short period, which seems to favour the sonoluminescence. In vacuum environment (0.1atm), an intensive sonoluminescence could be generated.
Temperature of a Compressed Bubble with Application to Sonoluminescence  [PDF]
S. Sivasubramanian,A. Widom,Y. N. Srivastava
Physics , 2002,
Abstract: The rise in temperature from the adiabatic compression of a bubble is computed in thermodynamic mean field (van der Waals) theory. It is shown that the temperature rise is higher for the noble gas atoms than for more complex gas molecules. The adiabatic temperature rise is shown to be sufficient for producing sonoluminescence via the excited electronic states of the atoms.
Water temperature dependence of single bubble sonoluminescence  [PDF]
Sascha Hilgenfeldt,Detlef Lohse,Willy Moss
Physics , 1998, DOI: 10.1103/PhysRevLett.80.1332
Abstract: The strong dependence of the intensity of single bubble sonoluminescence (SBSL) on water temperature observed in experiment can be accounted for by the temperature dependence of the material constants of water, most essentially of the viscosity, of the argon solubility in water, and of the vapor pressure. The strong increase of light emission at low water temperatures is due to the possibility of applying higher driving pressures, caused by increased bubble stability. The presented calculations combine the Rayleigh-Plesset equation based hydrodynamical/chemical approach to SBSL and full gas dynamical calculations of the bubble's interior.
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