This might be the easiest "particle physics without a particle accelerator" experiments you can do. This is your accelerator:<p><a href="https://en.wikipedia.org/wiki/Air_shower_(physics)" rel="nofollow">https://en.wikipedia.org/wiki/Air_shower_(physics)</a><p>And the muons produce two pulses in your detector, one when they are scattered to a stop and another when they decay. By measuring the time between the pulses you can fit the probability distribution and determine the half life of the mupn which is about 2.2 microseconds [1] And of course you can take measurements over time, at different altitudes and in different positions. If it wasn't for relativistic time dilation, muons would mostly decay high up in the atmosphere and not reach the ground.<p>This was one of the most popular experiments in the Physics 510 lab, which was the only class you had to take to get a Physics PhD at Cornell because it was so easy. It's also popular for high school physics for the same reason.<p>[1] <a href="https://en.wikipedia.org/wiki/Muon" rel="nofollow">https://en.wikipedia.org/wiki/Muon</a>
It's things like this that remind me there's always a little more to discover. I've built a number of those SBM20 geiger counters but I've never come across this muon detector design before. Seems to be a pretty well known design:<p>* <a href="https://www.hackster.io/jdpetrey/muon-detector-23bb72" rel="nofollow">https://www.hackster.io/jdpetrey/muon-detector-23bb72</a>
* <a href="https://www.madexp.it/2024/11/19/muon-and-geiger-counter/" rel="nofollow">https://www.madexp.it/2024/11/19/muon-and-geiger-counter/</a>
* <a href="https://iopscience.iop.org/article/10.1088/0031-9120/50/3/317" rel="nofollow">https://iopscience.iop.org/article/10.1088/0031-9120/50/3/31...</a><p>Pro tip - not all the SBM-20 tubes on Ebay are created equal! Some sellers will happily sell you tubes that are shorted, open, or just don't work. The better ones test their tubes.
My new favorite sciencey DIY site. It reminds me of the early Popular Mechanics and Scientific American projects. Now all I need is lots more time (or less responsibility). These are the sorts of things that should be available in middle and high schools everywhere.<p>edit: Adding a link to a page with a list of projects on the site.<p><a href="https://spectrum.ieee.org/topic/diy/" rel="nofollow">https://spectrum.ieee.org/topic/diy/</a>
My good friend convinced another friend to do this for a "small" uni project.
They showed it worked to a very impressed professor, only to shortly after discover (and not reveal to the professor) that it was disconnected and they were just seeing noise.<p>He passed away a few months after, but this sparked a smile in me.
When I have the time, I'd like to build an antenna to try to pick up the hydrogen line from space.<p>Just that simple thing is so strange to me, that with a handful of components you can listen to the cosmos. I really wish science classes would have included that sort of thing.
This is pretty cool.<p>The title here is incorrect; this is not tomography (and the OP doesn't claim it is). The article mentions tomography but what's happening here is individual measurements.<p>Tomography is also pretty cool, although the math is pretty painful (Terry Tao has papers on it)
Back when I was a physics student, I helped engineer exactly this experiment as a off-the-shelf solution for schools as a classroom experiment! We used PMTs mounted on top of coffee cans:<p><a href="http://kamiokanne.uni-goettingen.de/gb/kamiokanne.htm" rel="nofollow">http://kamiokanne.uni-goettingen.de/gb/kamiokanne.htm</a><p>The FTL muons produce Cherenkov radiation in the water in the coffee cans, which is picked up by the PMTs.<p>Using this setup gives a much higher rate, as the surface is much larger compared to geiger tubes. Thus it's possible to quickly capture a sufficient amount of muons.
Weird coincidence...I live roughly 2-miles from Reed Gold Mine. This sounds like a lot of fun, I look forward to trying this out. I also have family who are geologists, we spend a lot of time vacationing near abandoned mica mines, and our hiking is frequently scored by the chip-tuned sounds of my uncle's hacked Geiger counter (he rigged it up with an ADC and micro-controller so he can hear not only counts-per-second, but also some other metrics he has mapped to the tone's pitch).
I've wanted to make such a thing, but that got me thinking about a 6 tube design, three tubes on each layer in a # pattern, to get some angular resolution.<p>It also got me down the path of making a scintillation detector. However I've yet to find a hardware store source of scintillating material.<p>I kinda wanted something that didn't rely on a one-off source like asking my local uni for some scraps.
This may be a stupid question, but is this thing emitting anything or is it simply a passive detector? I’m mainly worried about any potential health risks.