Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×
Science Technology

Teen Builds Nuclear Bomb Detector 210

DaneM writes "An enterprising teenage boy named Taylor Wilson, 17, has created a homemade, hand-held nuclear bomb detector. It utilizes a small fusion reactor that he made when he was 14, and detects nuclear materials by shooting neutrons at closed containers and exciting any nuclear materials inside — which, in turn, causes more radiation to be produced, and is detected by the device. This may provide a simpler, more effective alternative to searching containers visually, one-at-a-time. No information is given about how safe such a practice is. Taylor also has some choice things to say about how science is, in fact, very cool."
This discussion has been archived. No new comments can be posted.

Teen Builds Nuclear Bomb Detector

Comments Filter:
  • by starfishsystems ( 834319 ) on Saturday June 18, 2011 @03:35AM (#36483780) Homepage
    Must be nice to have your own portable fusion reactor.
    • I wonder how much power it generates.

      • by icebraining ( 1313345 ) on Saturday June 18, 2011 @04:02AM (#36483896) Homepage

        Less than it consumes.

      • Fusor, not reactor (Score:5, Informative)

        by Roger W Moore ( 538166 ) on Saturday June 18, 2011 @10:19AM (#36485352) Journal
        I would guess that it is a Farnsworth-Hirsch fusor [wikipedia.org] which is a commercially produced device to produce free neutrons. In terms of application I'd be a little concerned what this device is used to probe. Neutrons are readily absorbed by many nuclei and can produce radioactive isotopes. So scanning an object will result in making it radioactive. While I would hope the number of neutrons required would be small, and so the activation minimal, this is still probably a concern for foodstuffs since radioactive material is a lot more dangerous inside the body than outside. Same applies for clothing too probably.

        The other issue is that since a nuclear device is a sub-critical mass of fissile material bombarding it with enough neutrons may actually make it supercritical while it is in the beam if the beam balances the neutrons lost. This would let you "detect" the bomb put perhaps not in a very constructive way...although again I would guess that the number of neutrons used for scanning would probably be too small to do this.
        • by cgenman ( 325138 )

          this is still probably a concern for foodstuffs since radioactive material is a lot more dangerous inside the body than outside. Same applies for clothing too probably.

          Radioactive clothing is definitely more dangerous inside the body than outside.

        • I would guess that it is a Farnsworth-Hirsch fusor ...

          Good news everyone!

    • Yeah, talk about your buried lead! The kid has fusion going for him, egads! TFA says he did the fusion thing 3 years ago, but is otherwise mute on the details. I'm no nuclear physicist, so I had to google to make certain my own understanding of nuclear fusion was in the ballpark.

      http://partners.nytimes.com/library/national/science/032399sci-cold-fusion.html [nytimes.com]

      Wait until Nature reads about this development at Gizomodo.com; they're gonna be pissed!

    • Re: (Score:3, Informative)

      by Anonymous Coward

      Seriously, people. Click all the way through to his actual article. Gods of Kobol--this is slashdot! Do it for Science!

      Not cold fusion. Not Science Fiction. Certainly not as exciting as it sounds.
      His fusion reactor:
      http://en.wikipedia.org/wiki/Farnsworth_fusor [wikipedia.org]

      • by nurb432 ( 527695 )

        its still cool that a kid that age has the interest to experiment at that level. Curiosity like this by youth is slowly being killed off, from several sources.

    • Re: (Score:2, Funny)

      by Anonymous Coward

      Next thing you know he'll be busting ghosts.

    • by Idbar ( 1034346 )
      Can you explain again, where in the airports are these detectors are going top be used? I can clearly see this can be helpful to the TSA... To get more budget again next year.
    • by PPH ( 736903 )

      When he turns 16, his parents will buy the DeLorean for him.

    • by sjames ( 1099 )

      I imagine it's a fusor. A fine source of neutrons, but it consumes more power than it generates.

    • The distinction is, this is a fusion reactor used to generate neutrons, not to be an electricity generator. It's the latter part that's such a difficult challenge.
  • by Anonymous Coward
    He used his *time machine* to make the nuclear fission reactor. Geez, some people are so cynical !
  • Built his own fusion reactor...excellent...and also figured out a way to make sure that the resulting neutron flux doesn't turn his carcass into a smouldering ash heap. Bonus.

  • Reality check (Score:5, Interesting)

    by pnot ( 96038 ) on Saturday June 18, 2011 @04:03AM (#36483902)

    As someone pointed out: building a fusion reactor, while not trivial, is routinely done by tinkerers worldwide: see e.g. this Instructables guide [instructables.com] .

    No, the truly amazing thing here is what I found when I clicked through to the original story [pbs.org] (as usual, not linked in the summary):

    ... here in Reno, we have the University of Nevada-Reno, and I went to the physics department. They offered to give me a bunch of parts, and after I got fusion, they offered to give me my own lab here to work in. So that was very helpful.

    Allow me to be the first to say, WHAT THE YELLOW RUBBERY FUCK? In every university department I've ever had experience of, researchers and grad students fight tooth and nail to get funding for anything more expensive than an alligator clip. Meanwhile, these guys have sufficient resources to start handing out equipment and lab space to enterprising teenagers for science fair projects! Hmm, time to start looking for a postdoc position there, I think...

    • by artor3 ( 1344997 )

      His own lab? Please tell me they didn't let a little kid in the lab unattended. Undergrads are bad enough.

    • Re:Reality check (Score:4, Informative)

      by Anonymous Coward on Saturday June 18, 2011 @09:26AM (#36485074)

      Taylor attends The Davidson Academy. A secondary school for profoundly gifted youth on the University of Nevada, Reno campus. My wife is his chemistry teacher. The Academy and University have a mutually advantageous relationship that allows motivated students like Taylor access to advanced resources not customarily accessible to the typical high school student.

      • by PPH ( 736903 )

        Do they have a football* team? This might explain why they have the time and resources to support gifted students.

        * Yeah, I know. What kind of football?

    • Re:Reality check (Score:4, Interesting)

      by Compholio ( 770966 ) on Saturday June 18, 2011 @09:33AM (#36485106)

      ... Meanwhile, these guys have sufficient resources to start handing out equipment and lab space to enterprising teenagers for science fair projects! ...

      A lot of funding agencies require a certain amount of your research budget to be spent on "educational outreach." It's likely that someone went "gee, here's a cool way to spend my outreach budget that won't require me to do anything."

    • Sometimes there is just stuff that's no longer useful for science, either because it can't be calibrated any more, or uses a technology that is no longer useful. But for someone tinkering, and not concerned about measurable, reliably repeatable outcomes, they can still be useful.

      For example I have an old oil based vacuum pump from a lab I used to work. It's no use in today's semiconductor physics, because things have gotten so small that the oil pollutes any experiment, and the vacuum it creates isn't high

    • They probably gave him older equipment that was due to be sold as surplus. It's easy to find that sort of thing on eBay or at university auctions for surprisingly low prices.

      As long as someone doesn't mind using a device that's a lot bigger and clunkier than the brand-new equivalent (and is off-warranty, and probably past due for calibration), it's a great way to get ahold of things that would normally be out of reach for non-professionals.

      The University of Washington has so much unwanted equipment like thi

  • Neutron radiation leads to neutron activation. I don't know off the top of my head what intensity of neutron radiation would be needed, but exposure which forms long-lived isotopes is cumulative. Common isotopes of iron, nickel and copper are all susceptible to some amount of activation.

    Cross-section to spall neutrons off of U238 or Th232 are ~1barn with halflife of days, but the most common isotope of iron has a n-2n cross section of around half a barn and the result has a halflife of several years. Any
  • Detecting nuclear bombs by shooting neutrons at it is like detecting dynamite by throwing fire at it right?

    • Re:Love it. (Score:4, Insightful)

      by ThunderBird89 ( 1293256 ) <zalanmeggyesi@y a h oo.com> on Saturday June 18, 2011 @04:15AM (#36483952)

      Nope, the bomb's fissile material is subcritical until the point of explosion, when it's compressed by an explosive charge (in crude terms, actually an explosive lens) into supercriticality. While subcritical, no amount of neutron bombardment will trigger it.

    • by azalin ( 67640 )
      You know that you can't set of dynamite that easily. Basicly the whole idea of dynamite is to have an explosive that doesn't blow in your face.
      C4 can even be used in some camping stoves to heat your dinner.
    • Detecting nuclear bombs by shooting neutrons at it is like detecting dynamite by throwing fire at it right?

      Yes, more or less. As actually dynamite is not exploding when thrown into fire. It just burns (not very good btw) off.

  • Okay, you might call it a fusion reactor, but it's just a fusor no matter how you look at it. It could most likely be replaced with any other neutron source, since what drives this is the neutron bombardment and the detection of induced radiation, the source of neutrons doesn't matter.

    Also, this is in no way revolutionary. What is revolutionary, however, is that the ICE and border guard hasn't managed to implement an automated neutron scanner yet, but a 17-years-old kid managed to. That is why I congratulate him, and hope the government takes notice of him.

    • "Okay, you might call it a fusion reactor, but it's just a fusor no matter how you look at it."

      How is a fusor *not* a fusion reactor? It is a device that causes nuclear reactions, even if it doesn't reach break-even in terms of energy output.

    • by BillX ( 307153 )

      Hmm... 17 year old kid playing with Teh Radiations, building fusors, shooting at potential fissile materials with neutron beams? From what I understand of our government, it will definitely, er, take notice of him.

  • If there is one thing not to mess with as a teen, it's nuclelar tech.

  • I love the Gizmodo link. Nothing like having a blank screen when I follow the link because I have to allow scripts on the page for simple text to show up. Nice. Good work on the post.
  • At first I thought the article was about this guy [blogspot.com], another teenager building a fusion reactor.
  • This could work (Score:5, Interesting)

    by mbone ( 558574 ) on Saturday June 18, 2011 @07:50AM (#36484626)

    Read the paper [sciradioactive.com]. He bought or built a "Farnsworth Fusor" to send 2.5 MeV neutrons into a package, and then look for high energy products of neutron induced fission from the package. These would be high enough in energy that the natural background would be quite low, making false positives low. There is no reason why this shouldn't work (although whether its practical is another question.)

    He tested it on "20 grams of Natural Uranium Trioxide (UO3) containing - 99.3% U238 and 0.7% U235." (In other words, about 0.1 grams of U235.) The integration time he found he needed was 10 minutes, rather than the 15 seconds desired by DHS, but it's an interesting concept. He doesn't do any calculations as to the expected return from an interesting about of U235 (say, 100 grams), but it would be higher, and so integration times should be less.

    He also says that the incident beam is low enough not to be harmful : "the system has low enough does as to not affect the health or functionality of the cargo and operator, However, he doesn't state any dosage information, which I would fault him on if I were grading this paper.

    • I can see a group of engineers being told " Okay this kid showed us a plan on how to make this thing you need to figure out how to make it work in the field UNLESS I SHOULD FIRE THE LOT OF YOU AND HIRE THIS KID AND HIS FRIENDS"

      maybe the dosage info is not present because he did not have/take the time to get enough data for a legally/medically sound figure??

    • Re:This could work (Score:5, Insightful)

      by thermopile ( 571680 ) on Saturday June 18, 2011 @11:59AM (#36485868) Homepage
      OK, Praise #1: This guy is awesome. He has the chops and wherewithal to build his own Farnsworth fusor by age 14.

      Praise #2: He's not satisfied with just building the thing, he wants to apply the thing. That's what I find truly commendable.

      So he goes off and learns a lot of good science and engineering in how to look for special nuclear material. Dennis Slaughter, of Lawrence Livermore National Lab, was featured on the front page of the American Nuclear Society's Nuclear News magazine [ans.org] in November of 2007 for his "nuclear car wash." Basically the same idea: use a neutron generator (a big one, in this case) and look for signatures of delayed neutrons in response.

      So, what Taylor has done isn't revolutionary, but I'm sure it's a lot cheaper than any other neutron active interrogation system out there. Good for him. And, again, awesome job for hunting for useful applications of technology.

  • by nurb432 ( 527695 ) on Saturday June 18, 2011 @08:51AM (#36484884) Homepage Journal

    Yes i agree, but its not approved knowledge by our federal government. Please come with us.

  • by account_deleted ( 4530225 ) * on Saturday June 18, 2011 @09:25AM (#36485070)
    Comment removed based on user account deletion
  • by Animats ( 122034 ) on Saturday June 18, 2011 @11:22AM (#36485698) Homepage

    This process is called neutron activation analysis. [wikipedia.org] It's well known. The practical problems are 1) not putting in so many neutrons that the tested object becomes radioactive, and 2) detecting enough emitted particles in a reasonable length of time. There's an obvious tradeoff there. The second problem is solvable with a large number of detectors, which probably means a portal or tunnel setup, rather than a hand-held device.

    Here's a commercial luggage screening machine [rateclab.com] from Russia which includes nuclear material detection by neutron activation, along with regular explosive detection.

  • At least not with non-homemade devices.
    Although it generates a neutrons, which pretty much ignore shielding, if it's portable it's not going to generate that much. Also, it's not a neutron detector.
    Now here's the fun part, properly manufactured nuclear devices are shielded to such a level you could use it to shield yourself from other radiation sources. They do NOT show up as radiation sources until you detonate them. Any neutron source that would cause the core to become so radioactive it can be detected i
  • Right, because we know that "small fusion reactors" can actually be built and run.
  • Snark on slashdot is business as usual. Being skeptical of the phrase "fusion reactor" tossed around lightly in the press is nothing to feel bad about. Why the writer wasn't more careful in phrasing the article to begin with is a more revealing question. Calling a fusor a fusion reactor misses the whole point of what a fusion reactor would be should one ever exist.

    Why no skepticism here, though, about the description of this purported "Little Man Tate" school:

    http://www.davidsonacademy.unr.edu/ [unr.edu]

    We're to b

To stay youthful, stay useful.

Working...