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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.
Induced radiation processes in single-bubble sonoluminescence  [PDF]
Fedor V. Prigara
Physics , 2005,
Abstract: According to the recent revision of the theory of thermal radiation, thermal black-body radiation has an induced origin. We show that in single-bubble sonoluminescence thermal radiation is emitted by a spherical resonator, coincident with the sonoluminescing bubble itself, instead of the ensemble of elementary resonators emitting thermal black-body radiation in the case of open gaseous media. For a given wavelength, the diameter of the resonator is fixed, and this explains the very high constancy in phase of light flashes from the sonoluminesing bubble, which is better than the constancy of period of a driving acoustic wave.
HBT Interferometry for Sonoluminescence Bubble  [PDF]
Y. Hama,T. Kodama,Sandra S. Padula
Physics , 1996, DOI: 10.1103/PhysRevA.56.2233
Abstract: The two-photon correlation of the light pulse emitted from a sonoluminescence bubble is discussed. It is shown that several important information about the mechanism of light emission, such as the time-scale and the shape of the emission region could be obtained from the HBT interferometry. We also argue that such a measurement may serve to reject one of the two currently suggested emission mechanisms, i.e., thermal process versus dynamical Casimir effect.
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.


中国物理 B , 1996,
Abstract: A non-adiabatic model of single bubble sonoluminescence has been advanced through considering the energy dissipation caused by light emission. The bubble dynamical equations with a black-body radiation have been solved numerically. The results show that without introduciag any model parameter, this model not only can well reproduce the experimental phenomena in the time scale of microsecond of the adiabatic model can do, but also can obtain a 40-100 ps of flash duration and a 104 K effective temperature of the black-body radiation. These agree with the experiment quite well.
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.
Comparison of Xe single bubble sonoluminescence in water and sulfuric acid

An Yu,

中国物理 B , 2008,
Abstract: Using the equations of fluid mechanics with proper boundary conditions and taking account of the gas properties, we can numerically simulate the process of single bubble sonoluminescence, in which electron--neutral atom bremsstrahlung, electron--ion bremsstrahlung and recombination radiation, and the radiative attachment of electrons to atoms and molecules contribute to the light emission. The calculation can quantitatively or qualitatively interpret the experimental results. We find that the accumulated heat energy inside the compressed gas bubble is mostly consumed by the chemical reaction, therefore, the maximum degree of ionization inside Xe bubble in water is much lower than that in sulfuric acid, of which the vapour pressure is very low. In addition, in sulfuric acid much larger $p_{\rm a}$ and $R_{0}$ are allowed which makes the bubbles in it much brighter than that in water.
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.
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