It's important to know the strength of the magnetic field so that we can calculate the momentum of the particles. The greater the magnetic field strength, the more the charged particles will curve.
The construction of this apparatus required a lot of soldering, at least for someone who has never soldered before, like me. Not to toot my own horn too much, but I think I did a pretty darn good job. Decide for yourself:
The magnetometer has a Hall Effect Sensor which has current running through it. The sensor is attached to a voltmeter, and when the sensor is inside a magnetic field the voltage changes, depending on the direction of the magnetic field. A change in 1 mV in the voltage is equal to 1 guass. The difference be the normal voltage and the experimental voltage gives you the magnetic field strength. I found the max field strength near the center of the magnet to be about 740 gauss (the Earth's magnetic field is about 0.5 guass).
We had a picnic lunch outside the physics building, and when we came back in we were ready to cool down our chambers for the first time. I didn't put enough alcohol in the ice box or in the reservoir in the tank, so I didn't see anything at first, but when I fixed those problems I started to see some tracks.
I wonder if a lot of the particles are being blocked because we are in the basement of a large building. Maybe when I take it home or use it at school we will get more tracks.
Someone decided we needed a radioactive source so we would be able to see a lot of tracks. We used the calibration source of a geiger counter to shoot gamma rays into one of the chambers. Here's what it looked like:
In that clip you should see the "cloud" which looks like fog or rain. If you look carefully you will see wisps in the cloud, which is caused when a cosmic ray ionizes the alcohol.
This isn't my chamber, but they are all basically the same. This video was shot at 720p, and I wish it could be a little clearer, so the next time I'll try 1080p, and probably 720p at 60fps after that.