Observing subatomic radiation at home - Cloud chamber

[Victor Boesen]

Me and my good friend in school are doing an exam about radiation, where we want to talk about background radiation from space and other gasses in our own homes(radon isotope 222). We decide we wanted to create a cloud chamber which shows particle radiation such as alpha and beta decay. We tried it two times, and today was by far the most succesful time. We could observe alpha-decay from radon gas and beta decay from other gasses including radon also.

An interesting screenshot I will leave below(the first one) shows a high energi beta decay(electron) which on its way hit another electron and therefor ripping it from its atom and leaving a little streak from the original electrons streak.

A little difficult to see, but the trail is from the top middle to the bottom right and the bulge is in the middle. Th same can be seen on the photo below, where the "destroyed" (it isn't destroyed but just knocked out of its shell) leaves a trail pointing downwards from the other electrons trail. Both trails are seen to the right in the image.

The next thing is also quite rare to catch. It is two alpha decays which comes from radon gas. This gas is emitted from the gro und as a result of decaying uranium, thorium and other types of rock in the ground. Alpha decay is easier to observe since alpha decay is a helium core(yes, this is how helium was discovered on earth after first being discovered in our sun) therefor it is a lot heavier and bigger.

Both trails are to be seen on the right side of the screen. One in the bottom and one in the top.

Another interesting thing that can be seen is a thing called "bremsstrahlung" which can be seen in the image below

To the left a beta decay can be seen but is very curled and it goes in many different directions and takes a lot of turns. Beta decay is made up of electrons so when they hit (they never come in contact with each other) another atom the electron will get slowed down and shot in another direction because of the charge of both parts. When this happens xrays are emitted. This phenomena is what makes the trail look like this.

Another thing which can be seen in a cloud chamber are muons, which are particles direct from space, but I have YET.... to find one of the is my footage. I have many other screenshots which I will leave below, but if you wish to learn more about how it works, just scroll right to the bottom of the page:-)

This is an ore of thorium which emits alpha particles as seen in this photo.

A cloud chamber isn't really that difficult to make if you can get dry ice and isopropyl alcohol. You are going to need these two components, an aquarium(any transparent container, preferably a good size for better trails), filt (a towel can also be used, as long as you can soak it in alcohol), led flashlights and a metal tray(a good heat/cold conductor would work the best, but we used a metal baking sheet:-). 
These will be put together in a way that looks like the picture above. Both dry ice in blocks and pills can be used, but I would prefer blocks since it is better for keeping the chamber level, and you could always brake the blocks to parts.

How does it work!!

The alcohol soaked in the felt at the top of the chamber will evaporate and fall to the bottom of the chamber but when it reaches the cold temperatures at the bottom of the chamber it liquefies again and gets super saturated. When a charged particle hits the alcohol it ionizes the alcohol particles and this makes the alcohol particles clump together almost like magnetising paper clips(they stick together even after removing the magnet). And that is it!

I hope you enjoyed this just as much as I did making the chamber(probably not, but you could try it for yourself) because it is really an amazing experiment if you are interested in the topic also if you are not. Thank you for reading if you read all the way to the bottom! If you want some of the footage from this I could send it to you in PM.

Kind regards, Victor

Clear skies and happy particle gazing? 

[niallk]

Absolutely fascinating!! Thank you for posting.  I must try this at some point if I can get hold of dry ice.

[Victor Boesen]

11 minutes ago, niallk said:

Absolutely fascinating!! Thank you for posting.  I must try this at some point if I can get hold of dry ice.

It is definitely worth trying it out!

[PeterW]

Vaseline glass marbles and thoriated welding rods can give you some activity.

Radon, are you in an area where it is prevalent? http://www.ukradon.org/information/ukmaps

the trails tend to waft very rapidly after formation, we used a demo Americium source do a dense number of short “hairy” traces that you could block with tinfoil (alpha). Good rig.

 

PEter

[Victor Boesen]

53 minutes ago, PeterW said:

Vaseline glass marbles and thoriated welding rods can give you some activity.

Radon, are you in an area where it is prevalent? http://www.ukradon.org/information/ukmaps

the trails tend to waft very rapidly after formation, we used a demo Americium source do a dense number of short “hairy” traces that you could block with tinfoil (alpha). Good rig.

 

PEter

I live in Denmark where radon can easily be found in the most of the country. I can share a photo later of an alpha decay from radon. Our uranium and thorium sources also worked very well.

[Desolation4all]

Nice work, I tried to develop a continuously working device with a team at the university where I study but lack of funds and a flawed basis left by the previous team. I did read some papers and I remembered that changing the gas inside the apparatus could help in trail formation, if you could get your hands on some argon and find a way to provide a pressure seal you could try if you get better trail formation.

[Victor Boesen]

1 hour ago, Desolation4all said:

Nice work, I tried to develop a continuously working device with a team at the university where I study but lack of funds and a flawed basis left by the previous team. I did read some papers and I remembered that changing the gas inside the apparatus could help in trail formation, if you could get your hands on some argon and find a way to provide a pressure seal you could try if you get better trail formation.

Thank you. I would really like to build one that functions an it better but it's limited what I can get my hands on at the moment. The reason I made this cloud chamber in the first place was because I had my final exams in 9th grade (don't know if it is the same in the Nederlands) and my topic was background radiation, but thank you very much for the advice! I really find it fascinating how you can observe elementary particles flying around at unimaginable speed, but also quite terrifying because it's slowly killing our body.

[Desolation4all]

It is a very interesting thing indeed, I also built one with my physics teacher for a visitor's day (for new students) in high school, ours did not work as well as yours did however. One interesting thing is that  the muons that form a significant proportion of the trails provide a test for special relativity (I did a paper in the final grade on that). Anyway, I also found the article I was talking about, here you go: hep.ucsb.edu/people/hnn/cloud/articles/ALangsdorfRSI10_91_1939.pdf

 

[Victor Boesen]

53 minutes ago, Desolation4all said:

It is a very interesting thing indeed, I also built one with my physics teacher for a visitor's day (for new students) in high school, ours did not work as well as yours did however. One interesting thing is that  the muons that form a significant proportion of the trails provide a test for special relativity (I did a paper in the final grade on that). Anyway, I also found the article I was talking about, here you go: hep.ucsb.edu/people/hnn/cloud/articles/ALangsdorfRSI10_91_1939.pdf

 

Sounds very interesting! Thank you for sharing with me, I will have a look at it.

[Macavity]

Really like this! I remember seeing one in action (school) a long time ago.
The "trails" have an additional (ironic) appeal... Like (plane)  contrails, they
form... drift... and then disappear! Harder to *photograph* as a result? ?

Ah, Radiation! Spent much of my studies / work using (often quite potent)
radioactive sources... And survived! lol. Most modern radioactive sources
are glassified / carefully contained etc. Sometimes I reread the following:

https://www.sciencealert.com/the-chilling-story-of-the-demon-core-and-the-scientists-who-became-its-victims-plutonium-bomb-radiation-wwii

Most peacetime LAB situations are rather safe. But a chilling reminder! ?

[Kn4fty]

Very cool! (Literally and figuratively). I'm going to try this! Thanks for the post and info!