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Build Your Own Cyclotron
mindpixel writes "Physics Today is running a story about Tim Koeth's 12 inch cyclotron. Here's a quote that says it all: 'I was sitting in Tom Devlin's modern physics lecture. He described the principle of the cyclotron. He said it required a lot of RF power. I was--and am--a ham radio operator, so RF was no problem. It needed a big magnet; I knew I could find one of those. How tough could a vacuum system and chamber be?'"
I made a cloud chamber in junior high (and I graduated from high school in 1972, so do the math.)
A little dry ice, some alcohol, black paper, a strong light, a petri dish (I think it was), and a bit of the stuff from the hand of a watch.
It actually worked; I could see an occasional trail of condensation, but the thrill was not that it worked but that I built it. I would not have been thrilled one bit less if it hadn't of worked at all.
Scientific American used to run article on how to build things for physics. Seems like prior to persuing chemistry and electrical engineering my brothers and I built Van Der Graff generators, cloud chambers, and lots more from those pages. They had an old design for a particle accelerator as well. It was NOWHERE near this.
Fascibnating to read an article like this
I'm going to make the king out of a linear accelerator. For the pawns I'll use my run-of-the-mill 5 keV cyclotrons.
A friend of mine in the physics program at Rutgers built the can crusher demo they have. It discharges a huge HV paper-oil capacitor through a coil of copper tubing about six or seven turns long, wrapped around a plexiglass tube. You put the can in the tube, close the switch, and POW the can is instantly crushed into a hot crumpled aluminum stick the width of your thumb because the field sets up a countercurrent in the can which repels the main coils. Even my girlfriend was impressed. We used to discharge the capacitor bank across thin wire-wrap wire, which vaporizes pretty well. He's working at some military contractor nowadays, working on ultrapowerful lasers. Which probably suits him better than the fiber optic sissy lasers he was working on before the telecom crash.
Another thing you should know if you take physics at Rutgers is that the physics auditorium is probably exposing you to mercury vapor. Legend has it that they did a "mercury hammer" demo one time with liquid nitrogen, where you pour the mercury in and freeze it, then pull it out and pound nails with it. Someone got the bright idea of passing the hammer around the room, and during its trip through the audience it started to drip. Only some of it made it back to the front of the room.
The Amateur Scientist volume actually had a small linear accelerator, not a cyclotron. A van de Graaf generator was coupled to a homebrew vacuum tube of the same height, with a filament in the base and a sample platform at the top.
What these guys did is a whole different kettle of fish. As cool as the Amateur Scientist accelerator article was, this cyclotron project is about 100x more complex and 1000x niftier. I wish I had the time, space, cash, and electricity to duplicate it!
Dahlmann tightly grips the knife, which he may have no idea how to use, and steps out into the plain.
The scary thing about the article is that it shows that 1930s/1940s technology is not the magic black art that most americans think. By that, I mean most americans are happy to think 'oh it takes such great amounts of technology and resources to build a nuke'... that was true - 60 years ago. For us to think that we've kept the lid closed on these types of weapons-technology only further pushes us into false senses of security. Its better that we strike now, blast everyone else into pre-stone age technology, so that the american Malls remain safe for all those dutiful shoppers.
The only PT Boat Journal on the web: http://www.PT171.org
I will resist making o/c comments on this post.
I will resist making fanboy comments on this post.
I will resist making riaa/mpaa comments on this post.
I will resist making political/outsourcing comments on this post.
I will resist making "that's nothing, i used to make my cyclotrons with a couple of diodes and a pizza box" comments on this post.
Amen.
That being said, it's a welcome change reading some genuinely good posts like this one (and the one on chess pieces yesterday). IMHO, one of the reasons that Americans should be proud of themselves is their ability and willingness to DIY just about anything. I hold people like Tim Koeth in higher regard than than any theoretical scientist anyday.
http://deseretnews.com/dn/view/0,1249,510054502,00 .html
It never seemed to me like it was actually fusion, but hey, whatever...
As a grad student in physics i've aided my professor in the construction of a VSM (vibrating sample magnetometer, 5T sweep field) and a low-temperature MOKE (magneto-optical Kerr effect) system which is housed in a vacuum chamber. I've had absolutely no fun dealing with hivac systems. So many parameters; such as the oil on your body, hair, microscopic defects in gaskets, and miniscule amounts of dust can really play a role on the vacuum that can be achieved. Then comes the fun of finding the leaks...ahhh! All in all, it was a good experience, though. So go build something. Take it easy.
I was at the International Science Fair back in 1995 in Toronto competing in the physics division. The guy next to me had built his own cyclotron and had done very well three out of the four years he competed in high school science fairs (which eventuall lead to the ISEF). Rumor was -- and this is only a rumor -- that he made himself ill with the radiation from the experiment. I'm not sure of the specifics but it is definitely worth being being careful before building your own cyclotron. I recall having looked into building my own at one point and determining that it would be dangerous.