# How does this happen?

1. Dec 24, 2007

### JanKo

Hello!

I recently found a picture (Here's the link:http://doc.cern.ch//archive/electronic/cern/others/PHO/photo-ex/66954B.jpeg" [Broken]) that is just a beautiful example of particle collision.
Now I get the general idea of what this picture is representing, but what exactly is happening here?
I mean, how would you explain this picture to a person who knows very little about physics?
Because I tried to explain it to my mother (because she loves the shapes ) and figured out that I actually have very little idea what's going on.

I know they use liquid hydrogen to create these bubbles around the paths of particles but that's about it.

So, please explain this to a person who knows little about particle physics... I guess that's me.

Last edited by a moderator: May 3, 2017
2. Dec 25, 2007

### malawi_glenn

It is just the Lorentz force, you dont have to be expert on particle physics, just know a fundamental law from electromagnetism ;)

Charged particles in motion bends in circular paths when subjected to magnetic fields, where the radius of the trajectory is proportional to the momentum (mass and velocity) of the charged particle. Also the direction of the bending reflects the charge of the particle, a positive charged particle bends the opposite way as a negative charged.

3. Dec 25, 2007

### JanKo

Thanks malawi_glenn for the pat on the back

One more question!
Does this happen by just smashing two atoms? Or did they collide more than two in this picture?
Because it looks to me as if there were a lot more than two atoms smashed...

4. Dec 26, 2007

### malawi_glenn

first of all, it is not atoms that they collide, in this picture it is probably electron - positron, or proton - proton collision.

And I think this picture can resemble one event, with background, showers (annihilation - creation) etc :)

http://en.wikipedia.org/wiki/Particle_shower