Science fair project

[1573]

I am a high school student who is working on a science fair project dealing with sonoluminescence, but I dont know what to do with it. Anyone have ideas or suggestions? Thanks.

[gpdone]

Welcome 1573!

Sonoluminescence is a very interesting phenomenon...and while I have read much about it and certainly have ideas concerning it and many, many questions..I for one feel the need for more information from you about where you are with the project and more speciific information about what you are asking for. For example, what is 'it'? Your project?, the topic sonoluminescence? or what? There are several very bright and generous people here who could help you better if you could be more specific.

Hope to hear more from you, gpdone.

[BlameTheEx]

luminescence triggered by sound? I believe some microscopic sea-life has that property.

[1573]

I want to work with sonoluminescence, but i don't know what I should investigate in this phenomenon. Many people have developed theories for what causes sonoluminescence. should I build upon a theory, develope my own, devise a way to take actual direct measurements of the phenomenon (from what I've seen most has been indirect), etc.. Thanks.

[Tormod]

Here's an experiment. Seems a bit tough but maybe you can get some ideas:

http://www.techmind.org/sl/

[1573]

Thanks, I came across that site in earlier research, and it provides a good deal of information to get started. I can probably aquire most of that equipment fairly easily. What I want to do though is work towards an original idea, or at least strong research that build on a previously though up idea. Would developing a way to view the phenomenon directly and visually contribute much to the research efforts? I'm not too sure how I could do that, since the cavitating bubble that produces the light is on the scale of a few micrometers at its widest. Maybe investigation into the possiblilities of fusion that have not been conducted yet? Most of this would be a bit ambitious for me, considering I only have a timeline of 2 -3 months to put all of this together into a nice neat little package for competition. Thanks

[GAHD]

You've definatly intrgued me with this, what other sources have you come across in you searches 1573?

(just hazarding a guess, but you birthday wouln't happen to be either January fifth or May first of 'seventy-three, would it?)

[1573]

Here is a government site that has some information on sonoluminescence, and an experiment they did:
http://www-phys.llnl.gov/N_Div/sonolum/
Here is a site with general information, and how to set it up:
http://www.physik3.gwdg.de/~rgeisle/nld/sbsl-howto.html

I got a good deal of my research at a local university, mostly science journals, and science magazine articles. Typing in sonoluminescence in google returns a lot of information; the sites above are just the ones I found to be most helpful on getting a general idea on the phenomenon. The thing about sonoluminescence is that no one really knows what causes it to happen. Theories on the source of light in sonoluminescence range from the idea that a small jet of water travels through the cavitating bubble at many times the speed of sound, and "fractures" the water in the same manner as a wintergreen mint releases light when it fractures, to the idea that the source of light is caused by fusion. It’s definitely an interesting phenomenon.

P.S. 1573 actually does not relate to my birthdate. Nice guesswork though

[GAHD]

i havn't dome more than glace at the articles at the moment, but it sounds to me like this phenominon is very simalar to the method used in old He-Ne tubes to make LASER beams.

"For unknown reasons, the addition of a small amount of noble gas (such as helium, argon, or xenon) to the gas in the bubble increases the intensity of the emitted light dramatically"
That quote made me think of a sciencefair project I did back in Grade 8 building a laser, it's a little out of topic so i've indented it so it can be viewed more as a sidebar.

Tube lasers function by having two mirrors positioned as close to paralell as possible, one mirror is 100% opaque while the other is 90-99% opaque. The gasses inside are excited by either a strong electrical current running through them or in the case of older versions, by having a 'flash lamp' wrapped around the tube in question that excites the atoms of the gas.

The excited gas emits specific frequency light in pulses when an electron get a little too charged and kicks itself up an extra valence layer. After a short period of time in this higher 'shell' the electron emits a photon based on how much extra energy it had and drops back to it's original layer. The photon(s) in question gets absorbed into other excited atoms, which then spit out two photons at the same frequency as the originator. The Current/flash ontinuously overcharges any unexcited molecules, and the domino effect continues untill the amplitude of the synched light wave is strong enough to pass right through the less opaque of the two mirrors.

What it sounds to me is happening in the case of these bubbles is that the frequency of sound is somehow exciting the atomic structure of the gas in question, causing it to emit light for a similar reason.

I'd say the sperical nature of the bubbles would act similar to the compression lense used in Fission bombs to make a shock wave that concentrates the entire force of the ignitor charge into the plutonium all at once, splitting that atom.

In this case it would make the gas charged with a high degree of kinetic energy focused on the center of the bubble. I could easilly see that kinetic energy turning to EM energy by friction. I could also see the larger waves causing much shorter oscilations in the bubbles themselves if they were too small to contain the overall wave.

If the tempurature does not cause enough expansion in the gas to overcome the surface tension the liquid in question, the pressure and energy would continue to build untill such time as the gases started sheding excess energy in the form of photons. The liquid could be reflective enough to send those photons back towards the center ofthe sphere untill such time as it reached a strong enough amplitude to brake through the shell in a single intence wave(flash).


The idea of a bubble pulsating in a standing wave facinates me because it implys that the frequency of sound is causing a harmonic frequency of strong amplitude photonic discharge that is self equiliberising. I might see one application as a very expensive clock.

[1573]

That's an interesting idea Ghad. I just read somewhere that adding an amount glycerin to the water increases the intensity of the light from the bubble by quite a bit. Any ideas on this? For now I'm just hoping those ultra high speed cameras (you know the ones that take 500 million frames per second) go on sale at walmart, so we can see just exactly what's going on here.