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Radioactive Boyscout

  1. Feb 28, 2005 #1


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    Possibly a topic of conversation here...

    Has anyone heard of this book / story? It really is amazing-scary. Possibly the most strange aspect about it, for me, is that it happened in my subdivision. I talked to a few neighbors who were there when things came to a head.


    The original Harper's article is here to save you from buying the book.


    It really is amazing how this kid got as far as he did.
    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Mar 1, 2005 #2


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    Actually, I'm not AT ALL impressed with the young Mr. Hahn's
    "accomplishments". First, the article states that, "..He had attempted
    to build a nuclear reactor in his mother's shed following a Boy Scout
    merit-badge project."

    If he studied a little physics and nuclear engineering - he would see that
    he went about his objective all wrong.

    The article states that he put his Am-241 source in a block of lead,
    presumably as shielding. If he had checked the Table of Nuclides, he
    would have found that the decay mode of Am-241 is by emitting Alpha


    If he had done his homework, he would have known that it is extremely
    easy to shield alphas - they won't penetrate a piece of paper!

    His knowledge of nuclear physics was faulty - witness his attempt at
    Al27(alpha,n)P30 - attempting to induce a spallation reaction on Al27
    with an alpha source? This kid must have been absent when they studied
    about like charges repelling in school.

    A reactor core is not just a bunch of radioactive materials all bundled
    together. A reactor core has materials and geometry chosen for a
    precise effect. The use of the word "critical" in describing a reactor is
    because a properly designed reactor is a delicate balance between
    neutron production and neutron loss. There was no understanding of the
    physics of what he was doing.

    This kid just assembled a bunch of radioactive material without any
    logic or plan that made any sense as far as the laws of physics are

    Dr. Gregory Greenman
    Last edited by a moderator: Apr 21, 2017
  4. Mar 1, 2005 #3


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    If you had read the story, you would have seen that he did this with, at best, a substandard high school education and, for the most part, one of his father's college science texts. This kid lacked every bit of sense on the planet, not just sense of the laws of physics. He was a degenrate. I was amazed he got as far as he did because of the happenings like how he posed as college professors and how he duped the NRC into giving him information.
  5. Mar 1, 2005 #4
    I have not finished reading the story, yet, but what was everyone worried about and why did they take such precautions, Morbius?
  6. Mar 1, 2005 #5


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    I DID read the story. I read it a long time back. We had this discussion
    some time back on one of the science newsgroups; sci.physics, if memory

    I was unimpressed then, and am still unimpressed.

    This kid set out to build a breeder reactor; and he had absolutely no
    concept of what a nuclear reactor was; let alone a breeder reactor.

    He thought if he just cobbled together some radioactive material in
    one spot - he would have a reactor.

    I remember reading a book called "The Atom: Today and Tomorrow"
    when I was in 5-th grade. I also used the address supplied in the back of
    that book to get more information from the then AEC's Division of
    Technical Information - including a booklet on "Nuclear Reactors".

    From those readings then, I had a better grasp as to what a nuclear
    reactor was, and how it worked; than this kid did.

    I would expect that a high school student - even one from a substandard
    school - to know enough to get some elementary texts on the subject
    of nuclear reactors before attempting to build one.

    No - this kid took the popular misconception that a reactor is just a
    pile of radioactive material - and ran with it.

    That doesn't connote anything praise-worthy, in my book.

    Dr. Gregory Greenman
  7. Mar 1, 2005 #6


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    They were worried about his materials, not his device.
  8. Mar 1, 2005 #7


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    Russ is correct.

    The worry is about the materials. He disassembled a number of smoke
    detectors in order to get the radioactive Am-241.

    The capsule that contains the Am-241 in a smoke detector contains a
    warning to the user not to open that capsule.

    It is just as if someone had run across a can of of arsenic, or some other
    poison, labeled with the traditional "skull and crossbones" denoting a poison.

    When one sees that symbol, anyone with a normal modicum of
    intelligence should know not to proceed unless they know what they
    are doing. The warning is there to protect you and the general public
    from the dangers contained within.

    This teen ignored those warnings and opened up the container. As long
    as the Am-241 was contained within - it was of no danger to the public,
    nor the teen. The alpha radiation that eminated from within the
    container is very short range - because it loses energy very quickly.
    That's why alphas can be stopped by a sheet of paper - or the dead layer
    of skin surrounding your body.

    Once the container is broached - then you have the prospect of someone
    ingesting the Am-241. The short range and high LET - linear energy
    transfer - of alphas [ meaning they transfer lots of energy per unit
    distance traveled ] that was once an advantage if the alpha source
    is external - now becomes a disadvantage.

    If the alpha source - in this case, Am-241 - is ingested; then the alphas
    are being emitted directly into living tissue. Because of the high LET -
    alphas do a LOT of damage locally. They can tear delicate molecules
    like DNA to shreds - and cause cancer.

    Returning to my analogy - if a poison is safely secured in a proper
    container - it is not a danger. If it is only removed from the container
    and handled by someone who knows how to handle poisons - so that they
    don't contaminate themselves and others; it is not a danger.

    However, if an amateur that doesn't know what they are doing - ignores
    the warning labels meant to protect them and the public in general - and
    proceeds to open the poison and handle it improperly - then that person
    is a public menance.

    I don't believe in heaping any praise on someone with such disregard
    for the dangers of poisons, nor radioactivity - especially when the
    "adventure" was as ill-planned, and ill-conceived; as the one under
    discussion here.

    Dr. Gregory Greenman
  9. Mar 1, 2005 #8
    "It seems remarkable that David's story hasn't already wended its way through all forms of journalism and become the stuff of legend" - From the article

    Stuff of legend? I don't think so... I never heard this story before and after reading it I can admire the kid's drive but the risk to himself and others in this manner isn't acceptable. Although he didn't need the lead shielding for the alpha radiation of the AM-241 (paper is enough to stop alpha as Morbius points out) the fact that he did it leads me to believe that he KNEW that the elements he was playing with were very dangerous. Also as soon as he realized that he was dedecting high amounts of radiotion through concrete and up to 5 houses away, he really should have told someone. It's one thing to put yourself in danger in the name of science but to knowingly risk many people around you isn't very ethical.
  10. Mar 2, 2005 #9
    Irène Joliot-Curie and the radioactive boy scout

    In 1935, Irène Joliot-Curie said she had induced neutron emissions via alpha irradiation of aluminum:

    • Aluminium can be transformed, by the capture of an alpha particle and the emission of a proton, into a stable silicon atom. On the other hand, if a neutron is emitted the product of the reaction is not a known atom.

      Later on, we observed that aluminium and boron, when irradiated by alpha rays do not emit protons and neutrons alone
  11. Mar 2, 2005 #10


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    I'm aware of that - but look at the ENERGY required to do that!!!!

    Before the alpha can get close enough to the nucleus of the aluminum
    atom for the alpha to be in range of the short ranged strong nuclear
    force - the alpha has to overcome the mutual electrostatic repulsion
    of the alpha and the nucleus. Therefore, there is a threshold energy
    that the alpha has to have. If the energy is below the threshold - the
    alpha doesn't make it close enough to the nucleus of the aluminum
    before it runs out of energy and stops. It has to have an energy greater
    than the threshold for the reaction.

    The Curies used Radium as their alpha source - with a higher energy
    alpha particle emission.

    The 5.6 MeV alpha from Am-241 is BELOW that threshold energy of
    the (alpha,n) reaction on Aluminum that the Curies induced. This is one
    of the things the teen should have looked up before he chose Am-241
    as his alpha source.

    He chose Am-241 because it was convenient to get from smoke detectors-
    NOT because it could do the job he intended it to do!

    Dr. Gregory Greenman
    Last edited: Mar 2, 2005
  12. Mar 2, 2005 #11
    I have done a little extra reading in my text about biological effects of alpha particles. Is ionization of water in the body or destruction and mutation of DNA a more pressing problem? Or are they one in the same?
  13. Mar 2, 2005 #12


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    Cells contain water. Radiation ionizes water (radiolysis) which then may recombine to form peroxide, a powerful oxidizer (oxidant). The oxidants then interact with larger molecules, and in the case of DNA, they may break it - hence mutations. Oxidants also interact with enzymes, proteins and other macromolecules necessary for cell function, and the cell may then 'die'.

    As the does of radiation increases, cell damage and mortality increase.

    If a person survives (i.e. does not die), there is still a risk of cancer.
  14. Mar 2, 2005 #13
    Interesting. Thank you for the clarification.
    Last edited: Mar 2, 2005
  15. Mar 2, 2005 #14


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    In your readings about the biological effects of alpha particles; you should
    come across a concept known as the "Quality Factor".

    With respect to radiation, the term "dose" means "how much energy is
    deposited per unit mass". The term "dose equivalent" is used for the metric
    that describes how much biological damage is done.

    The units of dose are "rads" [ = 100 ergs per gram ], or the SI unit is the
    "Gray" [ = 1 Joule per kilogram ].

    You get the "dose equivalent" by multiplying by the "quality factor".

    The units of dose equivalent are "rems" and "Sieverts".

    If you know the energy deposition dose in "rads" and you multiply by the
    quality factor - you get a dose equivalent in "rems" [ rad equivalent man ].

    If you know the energy deposition dose in "Grays" and you multiply by the
    quality factor - you get a dose equivalent in "Sieverts".

    So "rads" and "Grays" are both units for the same thing - and can be
    converted one to the other.

    "Rems" and "Sieverts" are both units of the same thing - and can be
    converted one to the other. You can see both of these units used
    side by side in the following table, courtesy of Idaho State University:


    [The unit "mSv" is the abbreviation for the milli-Sievert; 1/1000-th of a

    The quality factor for photons is 1.

    The quality factor for alphas is 20, if memory serves.

    Therefore, alphas do 20 times the amount of biological damage per
    unit of energy absorbed per gram; as do photons.

    Courtesy of the Institute for Energy and Environmental Research:


    Dr. Gregory Greenman
    Last edited: Mar 2, 2005
  16. Mar 3, 2005 #15
    He used Radium as his later alpha source, would that react with the Aluminum? What is a "spallation reaction"?
  17. Mar 3, 2005 #16
    Right said Fred and Irene

    We just went over that. Irène and Frédéric Joliot-Curie used radium to induce neutron emissions from aluminum. Here is Irène's Nobel lecture on the subject...

    ...and here is Frédéric's Nobel lecture on the subject:
    http://nobelprize.org/chemistry/laureates/1935/joliot-lecture.html [Broken]

    "...A nuclear reaction in which light particles are ejected as the result of bombardment (as by high-energy protons)." (M-W Unabridged 3.0.) Spallation is distinct from fission where spallation might be thought of as more of a brute-force reaction involving kinetic hammering by the spallating particle and fission as a more elegant reaction involving initially absorption by the target nucleus of the fission-inducing particle.
    Last edited by a moderator: May 1, 2017
  18. Mar 4, 2005 #17


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    You got it. On both counts.

    Dr. Gregory Greenman
    Last edited by a moderator: May 1, 2017
  19. Mar 5, 2005 #18
    Sorry, but what I meant was the way in which he obtained his Radium. Was it concentrated enough to use? I remember hearing in my high school physics class that otherwise, Radium was obtained by boiling off big pots filed with something that contained Radium but that only very little Radium was obtained in this way.
  20. Mar 7, 2005 #19


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    The "Radioactive boyscout" used Americium-241 [ Am-241 ] as the
    radioactive source of the alpha radiation.

    Am-241 is found in smoke detectors. The Am-241 emits alpha particles
    which are then detected by a radiation detector. Smoke interferes with
    the transport of the alpha particles. When the smoke detector observes
    that interference - it sounds the alarm.

    The boyscout dismantled a bunch of smoke detectors to get his source of

    Dr. Gregory Greenman
  21. Mar 23, 2005 #20
    The radium that this kid found was from an old clock he bought.

    "Inside he discovered a vial of radium paint left behind by a worker either accidentally or as a courtesy so that the clock's owner could touch up the dial when it began to fade. "- the story

    Disregarding any other stupidity, why choose radium? If he was such a chemistry buff, he should have read about how Frédéric Joliot-Curie got cancer from carying a vile of the stuff around in his pocket. Not fun stuff to handle.
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