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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?'"

53 of 187 comments (clear)

  1. Sounds dangerous by Anonymous Coward · · Score: 5, Funny

    I've seen Battlestar Galactica. First you build one, then it tries to kill you!

    1. Re:Sounds dangerous by Aardpig · · Score: 4, Funny

      I'd be hammering away every waking moment in my metal shop!

      You missed the 'n' before the 'k'.

      --
      Tubal-Cain smokes the white owl.
    2. Re:Sounds dangerous by Grey+Tomorrow · · Score: 4, Funny

      Sorry, the thread talking about the dangerous addictive nature of porn is one article over.

    3. Re:Sounds dangerous by barc0001 · · Score: 2, Insightful

      Slightly different
      If by different, you mean craptacular, then yes I have... ;)

      When I was a kid watching it during its original airing, I thought it was awesome. Seeing it again a couple of years ago I realized it didn't age very well, and a lot of it just didn't make sense to begin with. I vastly prefer the remake, myself.

    4. Re:Sounds dangerous by uberdave · · Score: 3, Informative

      In the books "The Cylon Death Machine" and "Battlestar Galactica", Cylons are a reptilian race and they wear body armour. As they progress through the ranks, some of them would be augmented with second brains. If they had the right body type, they would be awarded a third brain, and rise to the rank of Imperious Leader.

  2. Re:Yeah right by Anonymous Coward · · Score: 2, Funny

    Yeah, because you've got better things to do... like post on Slashdot.

  3. Next can some enterprising physics student do... by flint · · Score: 2, Funny

    an Orgasmotron?

    Any Dennis Miller Referentially-Challenged types please see http://imdb.com/title/tt0070707/. /.'ers especially could make use of that technology.

  4. Interesting.. by Anonymous Coward · · Score: 3, Funny

    I see "12 inch" and "vacuum" in the same story.

    Is /. posting spam now?

  5. "The magnet came to us ugly," by Timesprout · · Score: 4, Funny

    I fucking hate ugly magnets because I still find them almost as attractive as the cute ones.

    --
    Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
    What truth?
    There is no dupe
  6. Be careful with those Gamma Rays by Hulkster · · Score: 3, Funny

    I too was a mild-mannered scientist, until I was hit with an accidental dose of Gamma Rays and turned in The Incredible Hulk ... so Tim should be careful.

  7. cyclotron by That's+Unpossible! · · Score: 5, Informative

    n. A circular particle accelerator in which charged subatomic particles generated at a central source are accelerated spirally outward in a plane perpendicular to a fixed magnetic field by an alternating electric field. A cyclotron is capable of generating particle energies between a few million and several tens of millions of electron volts.

    --
    Ironically, the word ironically is often used incorrectly.
  8. Re:Next can some enterprising physics student do.. by Hentai · · Score: 3, Informative
    --
    -Hentai [in vita non pacem est]
  9. I made a cloud chamber once... by Anonymous Coward · · Score: 3, Interesting

    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.

    1. Re:I made a cloud chamber once... by Saint+Aardvark · · Score: 4, Interesting
      I used to have a copy of a book of Scientific American's Amateur Scientist columns that was published some time in the 50s -- back when they would not only give you instructions for making a cloud chamber, but offer a radioactive speck (!) for the price of a SASE (!!).

      They also had instructions there on building linear accelerators based on Van der Graaf generators. That wasn't good enough for me, though -- I wanted a circular accelerator, like they had at CERN. (Somewhere, between old report cards and essays on democracy, is a reply from Carlo Rubbia, head of CERN at the time, to a fan letter I wrote him.)

      I got as far as convincing the local welder that he should join some copper pipe in a circle for me for free. I'm great on ideas, but follow-through...Kudos to these guys for doing it. That's just cool beyond belief.

    2. Re:I made a cloud chamber once... by Concerned+Onlooker · · Score: 2, Funny

      That's a great junior high experiment. As an adult, however, you learn that you can make a cloud chamber using only the alcohol.

      --
      http://www.rootstrikers.org/
    3. Re:I made a cloud chamber once... by deglr6328 · · Score: 4, Informative

      pfft, this guy built a cyclotron IN HIGH SCHOOL by himself and used it to demonstrate "particle mass resonace" he won the ISEF (used to be westinghouse) with it. Oh and he also was a consultant on accelerator technology for the show "stephen hawkings universe" shown on bbc and pbs. Not cool enough for you. Well he also built a breeder reactor to win a scavenger hunt.

      --
      - "Hear that?! The percolations are imminent! Cease your ingress!"
  10. Oh, THAT'S why it's easy... by feloneous+cat · · Score: 2, Funny

    The recipe is:

    1. A bunch of RF (is that the metric or English "bunch"?).
    2. A large magnet (mine sez Acme, is that okay?)
    3. A vacuum system... Well I know of a woman who can suck chrome, so I guess that would be good enough.
    4. A chamber.... Okay yah got me stumped here sparky. Is a Altoids tin good enough?

    Hmmmm.... Or how about my ol' microwave oven? (2/4 requirements)...

    --
    IANAL, but I've seen actors play them on TV
    1. Re:Oh, THAT'S why it's easy... by orangesquid · · Score: 2, Informative

      Actually, you can do some preatty neat stuff with microwave oven parts... poke around billb's website for more info.

      --
      --TheOrangeSquid Is it any wonder things seem so awry? We swim in a sea of confusion and don't have to think to survive
  11. No Fair! by Jozer99 · · Score: 2, Insightful

    No fair, I thought there would be instructions!

  12. reminds me of all the old SA Amateur Scientist by Anonymous+Chemist · · Score: 3, Interesting

    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

  13. Cyclotron chess set by MillionthMonkey · · Score: 4, Interesting

    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.

    1. Re:Cyclotron chess set by Deadstick · · Score: 2, Funny
      Another thing you should know if you take physics at Rutgers is that the physics auditorium is probably exposing you to mercury vapor.

      Centuries ago I was doing a thesis project at an Air Force lab, and was measuring some pressures with a mercury manometer about six feet high, made of 1/4 inch ID tubing. If I had ever blown that thing, there would have been a couple of pounds of mercury skittering around on the concrete.

      Then a safety inspector came in and told me I had to put an overflow bottle on the manometer. So I did -- I taped a 2-ounce bottle to the top, connected it with a piece of Tygon, and the guy was happy.

      rj

    2. Re:Cyclotron chess set by Anonymous Coward · · Score: 2, Insightful

      Safety and Mercury are two terms that have only recently met. Around '76 in our suburban high school the physics instructor would bring out a plain old 6" wide glass jar (tin screw cap taped shut) half full of mercury and let each of us lift it a quarter inch off the counter to feel just how impossibly heavy a liquid could be.

      Great demo, but jeeeze... just one kid goofs and that jar would'a cracked wide. The god who protects fools did overtime back then.

    3. Re:Cyclotron chess set by MillionthMonkey · · Score: 2, Informative

      It's an impressive demonstration. Everytime I see it I still get spooked by the noise and spark it makes.

      So it's still there? That's impressive. He put it together 14 years ago. I thought it might have busted by now.

      His big problem was the switch. If you just use an ordinary switch, the capacitor bank discharges all its energy at the switch contact and ends up just destroying the switch and not crushing the can. He set up a system of two or three power transistors, where you push a button to flip the gate of the first transistor, and that one flips the gate of the next which flips the gate of the main HV power transistor that closes the circuit. He was still paranoid of getting a shock across the ten-foot lead wires so he surrounded the actual switch with lots of plastic and you pushed it down with a rubber tube. He should have used IR.

    4. Re:Cyclotron chess set by pyite · · Score: 2, Informative

      Hahaha, it's still there. I saw it last week. Here's the lecture notes to prove it. I did wonder about the pushing of the button with the tube, I thought that was kind of interesting.

      --

      "Nature doesn't care how smart you are. You can still be wrong." - Richard Feynman

    5. Re:Cyclotron chess set by MillionthMonkey · · Score: 2, Funny

      when my dad was in highschool he and his brother snuck into the chem lab and ended up dumping a jar of Hg all over the floor.

      Frank Zappa's father worked as a meteorologist at a military arsenal and used to come home with mercury for the kids. His autobiography talks about it: "One of the things I used to like to do was pour the mercury on the floor and hit it with a hammer, so it squirted all over the place. I lived in mercury."

      My father never brought home so much as a blob. I might have been a rock star by now. Gee, thanks Dad.

  14. Re:Next can some enterprising physics student do.. by Daktaklakpak · · Score: 2, Funny

    I think that would require you to build a 12-inch device of a different nature.

  15. Venkman... by Short+Circuit · · Score: 4, Funny


    Why worry? Each one of us is carrying an unlicensed nuclear accelerator on his back.
    </Venkman>

    Just seemed appropriate...

  16. Excellent story! by farrellj · · Score: 4, Insightful

    This goes to show you that you don't need megabucks to do good science! To many, half of science is the challenge, not the successes, but they are nice, of course [grin].

    I don't see why this mind-set couldn't be used for teaching science and computers on the high school level....Find a company that is getting rid of their dozens of old Pentium II system, get them to donate them to the highschool, and build a Beowulf or OpenMosix cluster to allow HS students to learn the fundamentals of supercomputing environments. Get a local university to help teach them...and you now have a chance of producing better educated computer geeks...and the physics & chemistry geeks and run small simulations as well.

    Just an idea...

    ttyl

    --
    CAN-CON 2019 - Ottawa's only book oriented Science Fiction Convention! October 18-20, Sheraton Hotel, Ottawa, Canada h
  17. 1930's technology by Anonymous Coward · · Score: 2, Funny

    1 MeV... 1 Million electron volts

    Zzzzzz

    The 1961 Bevatron was something like 6.5 Billion electron volts.

    What next, the guys build their own crystal radio?

    1. Re:1930's technology by HeghmoH · · Score: 2, Insightful

      If that's the state of the art in 1930's nuclear technology, then we should have guys building fission warheads in their basements around 2015.

      --
      Mod down posts with a "Free Mac Mini/iPod" sig, they're spam!
  18. Re:Next can some enterprising physics student do.. by Alien+Being · · Score: 3, Funny

    Miles Monroe: Perform sex? Uh, uh, I don't think I'm up to a performance, but I'll rehearse with you, if you like.

    Luna Schlosser: Okay. I just thought you might want to; they have a machine here.

    Miles Monroe: Machine? I'm not getting into that thing. I, I'm strictly a hand operator; you know, I, I... I don't like anything with moving parts that are not my own.

  19. Re:Next can some enterprising physics student do. by asr_man · · Score: 2, Funny

    Meloy implants the electrodes from this device into the back of the patient, at the bottom part of the spinal cord. When the electrodes are stimulated with a remote control, the brain interprets the signal as an orgasm, he said. The device is about the size of a pacemaker and can be turned on and off with a handheld remote control.

    As if men weren't already at a high enough risk of RSI.

  20. No big deal..... by CharlieG · · Score: 5, Informative

    Folks,
    Go out and get yourself a copy of "The Amateur Scientist" collection on CD.

    For those of you who are too young to remember the column, or before it was dumbed down, Scientific American had a column called "The Amateur Scientist" - they had plans for a cyclotron, a SERIOUSLY high power CO2 laser and LOTS of other things that could get you hurt in a real hurry. And they showed REAL experiments, and REAL science in that column.

    Of course, that was before SciAmerican got dumbed down, became half ads, and became PC - you could actually find desenting views in REAL papers

    --
    -- 73 de KG2V For the Children - RKBA! "You are what you do when it counts" - the Masso
    1. Re:No big deal..... by John+Miles · · Score: 2, Interesting

      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.
    2. Re:No big deal..... by CharlieG · · Score: 2, Informative

      Sept 1953 - cyclotron

      --
      -- 73 de KG2V For the Children - RKBA! "You are what you do when it counts" - the Masso
  21. Great! by DAldredge · · Score: 2, Funny

    Now those in DC will try to get /. banned because this is an evil, scary device that terrorists might use for SOMETHING... ;->

  22. Build it yourself... by RagingChipmunk · · Score: 2, Interesting

    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
  23. [partly OT] just some thoughts by asliarun · · Score: 2, Interesting

    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.

    1. Re:[partly OT] just some thoughts by geeber · · Score: 2, Insightful

      I hold people like Tim Koeth in higher regard than than any theoretical scientist anyday.

      I was with you, up until this point. Why place someone with an experimentalist bent higher (or lower) than someone with a theoretical one. They are both important, and without one, the other could not exist.

      I hold people who show intelligence, drive, and initiative in high regard, no matter what they choose to apply their interest to.

  24. This reminds me of another student story by thomas536 · · Score: 4, Interesting
    Fun with fusion: Freshman's nuclear fusion reactor has USU physics faculty in awe

    http://deseretnews.com/dn/view/0,1249,510054502,00 .html

    It never seemed to me like it was actually fusion, but hey, whatever...

    1. Re:This reminds me of another student story by sjames · · Score: 2, Informative

      It definatly is fusion, that's where the neutrons come from. Unfortunatly, causing that fusion to happen in this design requires a good bit more energy than the fusion reactions release. More unfortunatly, if there is a way to fix that, it's a very hard problem.

  25. Comment removed by account_deleted · · Score: 2, Informative

    Comment removed based on user account deletion

  26. Re:12" magnet weighing 2.5 ton? by MmmDee · · Score: 5, Informative
    Look for magnet details here.
    Height: 36 inches (91cm)

    Width:42 inches (106.5cm)

    Depth:12 inchs (30cm)

    Pole Diameter:12 inches (30cm)

    Yoke Cross Section:72sq.inches (450sq.cm.) per yoke (double that for total circuit area)

    Total Weight: 4,600 pounds

    -each coil:800 pounds

    -Iron:3,000 pounds

    Power Consumption (max. operating conditions): 4kW (80 V @ 50 A)

    Cooling Requirements: Water flow approx 2 GPM
    --
    No man's an island, unless he's had too much to drink and wets the bed.
  27. Re:wt of magnet by MmmDee · · Score: 2, Informative
    Magnet details
    Height: 36 inches (91cm)

    Width:42 inches (106.5cm)

    Depth:12 inchs (30cm)

    Pole Diameter:12 inches (30cm)

    Yoke Cross Section:72sq.inches (450sq.cm.) per yoke (double that for total circuit area)

    Total Weight: 4,600 pounds

    -each coil:800 pounds

    -Iron:3,000 pounds

    Power Consumption (max. operating conditions): 4kW (80 V @ 50 A)

    Cooling Requirements: Water flow approx 2 GPM
    --
    No man's an island, unless he's had too much to drink and wets the bed.
  28. Most everyone claims to have a 12" cyclotron... by Anonymous Coward · · Score: 5, Funny

    ...when most cyclotrons are only around 5.5 inches.

  29. Vacuum chambers will be the death of me. by DiracFeynman · · Score: 4, Interesting

    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.

  30. Re:Yeah right by mordors9 · · Score: 2, Funny

    Man do I feel stupid... when I was in college, I just sat around trying to figure out where to get beer and/or get laid. Of course most times I would have had as much success in building the cyclotron.

  31. Re:What does it do? by mindbomb33 · · Score: 2, Informative

    I think this explains it:
    Cyclotron
    maybe.

    --






    --
    "You've only got one finger left,
    and it's pointing at the door."
  32. Re:Yeah right by isaac · · Score: 3, Informative
    yeah, i'm curious too. If it's 12in diameter and say 2 feet tall from that picture (if it's taking all the vertical space in the frame). Then I come up with it weighing ~800 lbs if made of iron. I would guess it's made of some crazy ceramic type matarial, still don't see it making 1.5 ton, would have to have a density of ~1.0 lb/in^3

    The pole diameter is only 12 inches but the yoke and coils are included in that figure. Total weight is 4600 lbs for the magnet assembly - each coil is 800 lbs and the iron yoke and pole assembly is 3000 lbs.

    http://www.physics.rutgers.edu/cyclotron/12inchmag .shtml

    -Isaac

    --
    I am not a lawyer, and this is not legal advice. For Entertainment Purposes Only.
  33. Re:Problems arise, and this is GOOD for education. by PoopJuggler · · Score: 2, Funny

    Duh. All they need to do it tweak the modulation of the dilithium intercharger and it should increase their power output to within 6 megajoules of the optimum phase dispersion. Jeez, they teach this stuff in Basic Warp Drive Physics 101 at the Academy...