I finished a MSC in nuclear physics then during a student trip to the museum « Visiatome » near Avignon in 2008, I saw a PJ45 cloud chamber.
In university, we studied pages and pages of nuclear physics theory. This was interesting, but boring. It’s the physics of infinitesimal world, with particles traveling nearly at speed of light : this is just impossible to feel it in our macroscopic world. Practical classes were just to use Geiger counters or computer simulated programs to check the equations.
I studied sciences in university for 8 years and never a teacher, a book or Internet (in 2009 cloud chambers were not common) did mention about this wonderful experiment. During my student life I built dozens of sciences experiments and have interest in a lot of domain : I thought I known a lot in science. Then I saw the existence of such experiment by chance, coming from nowhere. This machine, forgotten by most of the minds, had the humble task to reveal an invisible world : the difficult equations or annoying theories just becomes clears and logicals, just by seeing the interactions in the cloud.
So who is to blame ? my teachers who spent so much energy to stuff us pages of nuclear physics without using the right pedagogical tools ? me because I didn’t make enough research in my domain of studying ? there is only one culprit : time. No one have time to check the bases, but the answers are always there. Only the up-to-date technology is worth our attention. Since his invention in 1912, cloud chamber was simply forgotten as time passed and was relegated in sciences museums. It was the case in 2008 when I accidentally see one in a museum.
10 years later, cloud chambers are very common. Maybe I contributed a bit with all the thermoelectric pioneers to make it a valuable science project and an useful pedagogical tool. I’m really happy that nowadays clouds chambers are put under the spotlights and have the merits they truly deserve. « The most original and wonderful instrument in scientific history » I can’t be more agree with that. Even now, I just simply don’t understand how it’s possible to see so easily, the quantum world. I always thought is was something theoretical and inaccessible, but with some raw materials, anyone can force this world to show.
Back in 2008. At this time, I was frustrated with this visit, particularly about my ignorance. In the bus, returning to the university, I said I have to build one. I asked the price of the machine I saw : 29 k€. Ok, this explain why our university didn’t have one to play with. It would be awesome, if our university or college had this type of experiments. It would simplify the understanding of abstracts theories and change the perception of our world, showing that radioactivity is anywhere. But we didn’t have any.
So I decided to put all my energy and time to study cloud chambers. My goal was to democratize them in different manner :
- make tiny, affordable cloud chamber for school projects (see this page to build one),
- build a website which explain what we see and what we can experiments in a cloud chamber.
- make a reliable machine, which can work for years, dedicated to university/college to study nuclear physics, at an affordable price (/5 the regular amount asked by some companies).
It began with aircooled then watercooled thermolectric cloud chambers. I got more and more confident about the behavior of supersaturated environments, how to set them and obtain the right equilibrium. I learned that by doing numerous iterations of machines until I had satisfactory results. The ancients articles and reviews published by scientifics of the last century were precious and uncontournable indications too.
The final developments are slow because as I work as engineer in the nuclear industry, I have to make frequent displacements. But surely, the most difficult part has been done, and I hope by the end of 2020 that my definitive built will be ready.