Geometry.Net - Science: Sonoluminescence

Sonoluminescence
De Montfort University
http://www.cse.dmu.ac.uk/~ake/Research/sonoluminescence.html

Extractions: Allan Evans, Xin-Kai Li, Ursula Augsdorfer, David Oxley Sonoluminescence is a remarkable phenomenon where light is produced by a liquid when it is stimulated by sound waves. The mechanism involves small gas bubbles in the liquid, which expand and collapse in response to the variations in pressure caused by the sound. When a bubble collapses violently enough, light is emitted. Sonoluminescence can be produced either in 'cavitation fields' containing many bubbles (this is known as multi-bubble sonoluminescence) or by trapping a single bubble in a controlled ultrasound field. We are actively engaged in experimental and theoretical work on sonoluminescence. The picture on the left shows a bubble trapped by an ultrasound field in a glass flask, and illuminated by laser light. (The bubble is the orange dot in the centre of the flask, near the edge of the laser beam). Part of the mechanism for the concentration may be a spherical shock wave which is launched by the bubble surface as it collapses. The shock converges on the centre of the bubble, becoming more intense as its energy is focussed on a point. We have analysed the stability of the spherical shape of these waves using an approximate theory of shock propagation. See A.K. Evans, Physical Review E Another topic of interest is the devation of sonoluminescing bubble from a spherical shape. The highly nonlinear bubble motion causes instabilities which magnify small thermal deviations. We have modelled how thermal noise influences the bubble, using a stochastic differential equation for the dynamics of modes of distortion. The results of simulations show excellent agreement with experimental results (U.H. Augsdorfer, A.K. Evans and D.P. Oxley: Physical Review
SONOLUMINESCENCE LINKS
For a page which is being actively maintained, but covers only review papers, see the Net Advance sonoluminescence Page.
http://web.mit.edu/afs/athena.mit.edu/user/r/e/redingtn/www/netadv/sl.html

Extractions: NOTE: Due to lack of time, this page is not being updated. For a page which is being actively maintained, but covers only review papers, see the Net Advance Sonoluminescence Page. General Empirical Apparatus ... Quantum Electrodynamic Theories GENERAL: EMPIRICAL: Various Liquids: Light-Emitting Region: THEORIES OF SONOLUMINESCENCE: Quantum Electrodynamic Theories: Unruh Effect in Bubbles: ASTROPHYSICAL SONOLUMINESCENCE: ELECTROMAGNETIC EFFECTS: HIGH ENERGY EFFECTS: Particle Production: MULTIPLE-BUBBLE SONOLUMINESCENCE: RETURN TO CONDENSED MATTER PAGE To contribute to this page, write Norman Redington, redingtn@mit.edu.
Sonoluminescence At TU Darmstadt
sonoluminescence We do quite a lot of experimental and numerical work aboutsingle bubble sonoluminescence (SBSL). Boosting sonoluminescence.
http://www.physik.tu-darmstadt.de/nlp/sl/

Extractions: SBSL cell Some selected subjects: Shock Wave emissions of a Sonoluminescing Bubble Boosting Sonoluminescence Sonolumineszenz und 2-Frequenzanregung Sonolumineszenz von Einzel - und Mehrblasensystemen - Diagnostik und Optimierung - ... Sonolumineszenz: Instabile Diffusion und chemische Reaktionskinetik
Robert Mettin Cavitation And Sonoluminescence
R. Mettin and J Holzfuss, Optimierte akustische Anregung der Sonolumineszenz(Optimized acoustic excitation of sonoluminescence) , in Fortschritte der
http://www.physik3.gwdg.de/~robert/cav.html
Symposium On Sonoluminescence
University of Chicago Chicago, Illinois
http://mrsec.uchicago.edu/MRSEC/meetings/sonoluminescence/
Latest Research Results In Sonoluminescence
Latest Research Results in sonoluminescence. University of light. Thisphenomenon is called single bubble sonoluminescence (SBSL). Two
http://www.tn.utwente.nl/wsl/research/sonoluminescence/resonoluminescence.html
Christopher Petersen's Page
Chris Petersen (University of California Santa Barbara)
http://members.aol.com/cpeter2001/science2/index.htm

Extractions: Hello, my name is Chris Petersen. I am a Physics major at the University of California Santa Barbara and no longer at Shasta College in Redding, CA. While at Shasta College I completed an independent study on single bubble Sonoluminescence (SBSL). Under Tom Masulis and Joe Polen, Douglas Manning and I were successful in making Sonoluminescence. Sonoluminescence was discovered by accident (like most applications in science) in the early 1930's by a pair of German Physicists @ the University of Cologne. It hasn't been until the last ten years that theorists and researchers have really given sonoluminescence an audience. The leading work has being done by Seth J. Putterman, Robert A. Hiller and Bradley P. Barber at UCLA. While this group has published many papers on sonoluminescence the most popular of their papers can be found in Scientific American Feb. 1995 Vol.272. The phenomenon of single bubble sonoluminescence can be produced as a table top physics project. From 100 to 200 dollars one can make sonoluminescence. To make SBSL (Single Bubble Sonoluminescence) one has to have a bubble (of plain air) surrounded by water in a spherical flask and then bombarded by high frequency sound waves. This causes the bubble to contract and as this happens something very spectacular happens! The bubble starts emitting light. Light, as in photons are being emitted from this bubble of air (now plasma) that is under contraction. I hope that you are as amazed as I was the first time I learned of this effect (that is if you are not already looking for info on SL).
SONOLUMINESCENCE LINKS
sonoluminescence RESEARCH. For a page which is being actively maintained, butcovers only review papers, see the Net Advance sonoluminescence Page.
http://web.mit.edu/redingtn/www/netadv/sl.html

Extractions: NOTE: Due to lack of time, this page is not being updated. For a page which is being actively maintained, but covers only review papers, see the Net Advance Sonoluminescence Page. General Empirical Apparatus ... Quantum Electrodynamic Theories GENERAL: EMPIRICAL: Various Liquids: Light-Emitting Region: THEORIES OF SONOLUMINESCENCE: Quantum Electrodynamic Theories: Unruh Effect in Bubbles: ASTROPHYSICAL SONOLUMINESCENCE: ELECTROMAGNETIC EFFECTS: HIGH ENERGY EFFECTS: Particle Production: MULTIPLE-BUBBLE SONOLUMINESCENCE: RETURN TO CONDENSED MATTER PAGE To contribute to this page, write Norman Redington, redingtn@mit.edu.
The Effect Of Anomalous Mass Flux On Expansion Ratio And Light Emission Ratio In
D. Felipe Gaitan National Center for Physical Acoustics, University of Mississippi, University, MS 38677 R. Glynn Holt Boston University, Dept. of Aerospace and Mechanical Engineering, Boston, MA 02215
http://home.olemiss.edu/~gaitan/html/recent_paper.html

Extractions: Dependency of light intensity on the mechanical response ... Top Abstract Single bubble sonoluminescence (SBSL) in an air-water system has been shown to occur along a unique surface in the parameter space, constrained by the requirements of shape and mass flux stability. In this paper, we show that diffusive dynamics apparently governs the mass flux stability. We present measurements of the expansion ratio for bubbles near the threshold for light emission. The results suggest that bubble radial response is an insufficient criterion for the onset of light emission, and we present evidence for the dependence of the emitted light on bubble dynamics. [PACS: 43.25.Y,47.55.Bx,42.65.Re,47.52.+j] The Effect of Anomalous Mass Flux on Expansion Ratio and Light Emission In Single-Bubble Sonoluminescence Single bubble sonoluminescence (SBSL) is a phenomenon in which an acoustically levitated bubble is made to oscillate so violently that pulses of light are emitted at the time of collapse (1). As described in a previous paper (2), SBSL occurs in a small window of the acoustic pressure-ambient radius (Pa, R0) (3) parameter space. In that article, SBSL was defined such that 1) the bubble remains spherically symmetric (except perhaps temporarily during the final stages of the collapse (4)) and 2) the ambient radius (R0) does not change significantly during time scales of millions of cycles. Also, it was shown how degassing the host fluid for obtaining SBSL (dissolved air concentrations Ci / C0 ¾ 0.50 in water, where Ci is the concentration far from the bubble, and C0 is the saturation concentration at ambient temperature and pressure) constrains the path of stable bubble oscillations to a series of points in a V-shaped curve with its vertex toward the left (
Sonoluminescence Active Waveform Control
Two kinds of closed loop feedback control are proposed for modifying the acousticexcitation that gives rise to the phenomenon of sonoluminescence (SL).
http://www.wdv.com/Notebook/Sono/AWC.html
Sonoluminescence Experiment: Sound Into Light
W.A. Steer's account of his work to construct apparatus to enable the observation of sonoluminescence, to investigate its basic properties, and leave a kit and instructions to form the basis of a future finalyear undergraduate experiment.
http://www.techmind.org/sl/

Extractions: About... Sonoluminescence is a little-understood phenomenon whereby light is emitted by tiny bubbles suspended in a liquid subjected to intense acoustic fields. The aim of this work was to construct apparatus to enable the observation of sonoluminescence, to investigate its basic properties, and leave a kit and instructions to form the basis of a future final-year undergraduate experiment. It was found that despite the apparent simplicity of the setup, to obtain successful and repeatable sonoluminescence required great care in the selection and tuning of system components, and a good degree of patience. The widely-reported increase in bubble brightness at low temperatures was readily confirmed, and a simple Mie scattering arrangement configured to monitor the bubble size gave results consistent with those already published. Sonoluminescence was first observed in an ultrasonic water bath in 1934 by H. Frenzel and H. Schultes at the University of Cologne, an indirect result of wartime research in marine acoustic radar. This early work involved very strong ultrasonic fields and yielded clouds of unpredictable and non-synchronous flashing bubbles, now termed "multi-bubble sonoluminescence". Such a chaotic phenomenon did not lend itself to detailed scientific investigation. Study of sonoluminescence then made little progress until 1988, when D. Felipe Gaitan succeeded in trapping a stable sonoluminescing bubble at the centre of a flask energised at its acoustic resonance - single-bubble sonoluminescence (SBSL). However their interest soon waned, and the research was subsequently taken up by Dr S. Putterman et. al., at UCLA, California.
Plasma-Material Interaction Group
sonoluminescence Overview and Future Applications. Introduction. The brilliant blueglow in the picture above is one of many examples of sonoluminescence.
http://starfire.ne.uiuc.edu/~ne201/1995/levinson/sonolum.html

Extractions: Quick Links Advisor Objective Research Areas University Courses ... Webmaster The brilliant blue glow in the picture above is one of many examples of sonoluminescence. The scientific-sounding word basically translates to "sound into light." The idea is very simplea small bubble, surrounded by some liquid, is bombarded with sound. Due to the high energies now in the bubble, it starts to luminesce, or produce light. When researchers first discovered this phenomenon, they called it sonoluminescence While sonoluminescence was first discovered in the 1930's, it received little attention until recently. In the past few years, a number of discoveries have been made, opening up even more mysteries. While most people have heard nothing about sonoluminescence, it has great potential in many scientific areas. High on the list for many researchers is its applications to fusion , since it is predicted that as sound bombards a bubble, the temperatures can get so hot as to allow fusion to occur within the bubble. Accordingly, there is some exciting research going on in this new field, and, according to Science , it is "a remarkable laboratory for physics and chemistry." [
Sonoluminescence Experiment: Sound Into Light
Detailed explanation of how I configured apparatus for the observation of sonoluminescence. Preparationof a flask for use as a sonoluminescence vessel.
http://www.techmind.org/sl/sono.html

Extractions: About... Sonoluminescence is a little-understood phenomenon whereby light is emitted by tiny bubbles suspended in a liquid subjected to intense acoustic fields. The aim of this work was to construct apparatus to enable the observation of sonoluminescence, to investigate its basic properties, and leave a kit and instructions to form the basis of a future final-year undergraduate experiment. It was found that despite the apparent simplicity of the setup, to obtain successful and repeatable sonoluminescence required great care in the selection and tuning of system components, and a good degree of patience. The widely-reported increase in bubble brightness at low temperatures was readily confirmed, and a simple Mie scattering arrangement configured to monitor the bubble size gave results consistent with those already published. Sonoluminescence was first observed in an ultrasonic water bath in 1934 by H. Frenzel and H. Schultes at the University of Cologne, an indirect result of wartime research in marine acoustic radar. This early work involved very strong ultrasonic fields and yielded clouds of unpredictable and non-synchronous flashing bubbles, now termed "multi-bubble sonoluminescence". Such a chaotic phenomenon did not lend itself to detailed scientific investigation. Study of sonoluminescence then made little progress until 1988, when D. Felipe Gaitan succeeded in trapping a stable sonoluminescing bubble at the centre of a flask energised at its acoustic resonance - single-bubble sonoluminescence (SBSL). However their interest soon waned, and the research was subsequently taken up by Dr S. Putterman et. al., at UCLA, California.
[hep-th/9901011] The Casimir Effect: Physical Manifestations Of Zero Point Energ
Kimball A. Milton High Energy Physics Theory, abstract (hep-th/9901011) Is there a connection between the Casimir effect and the phenomenon of sonoluminescence?
http://xxx.lanl.gov/abs/hep-th/9901011

Extractions: Zero-point fluctuations in quantum fields give rise to observable forces between material bodies, the so-called Casimir forces. In these lectures I present the theory of the Casimir effect, primarily formulated in terms of Green's functions. There is an intimate relation between the Casimir effect and van der Waals forces. Applications to conductors and dielectric bodies of various shapes will be given for the cases of scalar, electromagnetic, and fermionic fields. The dimensional dependence of the effect will be described. Finally, we ask the question: Is there a connection between the Casimir effect and the phenomenon of sonoluminescence? References and citations for this submission:
PhysicsWeb - Sound Waves Size Up Sonoluminescence
Sound waves size up sonoluminescence 5 February 2002. When a gasbubble trapped in a liquid is destroyed by a sound wave, it can
http://physicsweb.org/article/news/6/2/3

Extractions: Sound check The pressure variations of a sound wave can make a gas bubble in a liquid periodically shrink and grow. At certain temperatures and pressures, the bubble may implode to generate a huge pulse of energy, which leads to the emission of photons. Many physicists believe that the gas inside the collapsing bubble is rapidly compressed and becomes so hot - typically 20 000 to 30 000 kelvin - that it becomes a plasma. Most studies of sonoluminescence have focused on the effect of adjusting the pressure on the gas bubble - that is, using different frequencies and intensities of sound waves. But these experiments have been hampered by the narrow range of conditions under which sonoluminescence will take place. According to Fink and co-workers, their technique overcomes these limitations. They filled a spherical glass cell with water and trapped an air bubble by focusing a 28 kHz standing wave onto it. This caused the bubble to oscillate in size between 5 and 50 micrometres in radius. Just as the bubble was about to collapse, the team switched on eight 700 kHz generators that were evenly spaced around the cell. These signals interfered constructively with the lower-frequency waves and made the bubble collapse more quickly, emitting nearly twice as much light as it did without them.
PhysicsWeb - New Light On Sonoluminescence
New light on sonoluminescence 1 April 1999. The origin of sonoluminescence the emission of light by bubbles of gas trapped in a
http://physicsweb.org/article/news/3/4/3/1

Extractions: 1 April 1999 The origin of sonoluminescence - the emission of light by bubbles of gas trapped in a liquid and excited by sound waves - is one of the big mysteries in physics. In a typical sonoluminescence experiment the bubble can expand to a size of up to 50 microns and then collapse to a radius of less than a micron, all within 50 microseconds or so. Short flashes of light are emitted at the minimum radius. Until recently the fact that the bubble remained stable had puzzled researchers. Now a simple extension of the hydrodynamic/chemical model that can explain this stability can also explain most of the properties of the light emissions as well ( Nature Sascha Hilgenfeldt, Siegfried Grossman and Detlef Lohse extended the model by making the bubble's temperature dependent on its volume and by making an allowance of the small emissivity of the weakly ionized gas inside the bubble. The latter term allows for the fact that experiments have shown that only Nobel gases remain inside the bubble during sonoluminescence. According to their model, sonoluminescence is caused by thermal bremsstrahlung (energy produced by ionised particles changing their velocities) and recombination. In the latter process positive ions and electrons recombine and release their excess energy as photons.
Research On Sonoluminescence In The Department Of Mathematical Sciences.
De Montfort UniversityCategory Science Technology Ultrasound sonoluminescence
http://www.cms.dmu.ac.uk/~ake/Research/sonoluminescence.html
Sonoluminescence
One of the key unsolved problems of physics relates to the motion ofcontinuous media and can be formulated as follows Why is there
http://www.physics.ucla.edu/Sonoluminescence/
Page 3: Sonoluminescence
sonoluminescence For an account at the level of a science graduateplease see the article in Physics World on this site. For an
http://www.physics.ucla.edu/Sonoluminescence/page3.html

Extractions: Sonoluminescence For history see the above articles and the thesis of Lofstedt UCLA 1995, and a letter to Physics World August 1999 at this site. We believe that the photo of a single light emitting bubble moving in a torus generated the appearance of a shuttlecock as reported in the thesis of Paul R. Temple U. Vermont 1970 who we credit with the first observation of sonoluminescence from a single bubble. Latest results include the use of a streak camera to observe the emission of an outgoing shock wave from the sonoluminescing bubble. In a 16KHz sound field the strength of the shock wave approaches 1 Million Atmospheres. Two color plates and a black and white show the experiment and data. Physical Review E 2000. Sonoluminescence has found use in synchronizing photodetector arrays for the solar neutrino observatory and in plastic surgery.
CIMU- Sonoluminescence
sonoluminescence sonoluminescence refers to the transduction of sound energyinto light energy, mediated by bubbles in a supporting fluid.
http://cimu.apl.washington.edu/sono.html

Extractions: Sonoluminescence refers to the transduction of sound energy into light energy, mediated by bubbles in a supporting fluid. The figure below illustrates the nonlinear radial response of a single bubble to an applied sound field. When the pressure within the bubble falls below the vapor pressure of the liquid, the bubble begins to grow while the bubble fills with vapor. When the pressure turns positive, the vapor condenses and the bubble accelerates rapidly inward. Near the minimum radius, the bubble may emit a flash of light. The bubble continues to oscillate near its resonant radius, until the next acoustic cycle, where the entire process repeates itself.

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