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Nuclear Sources of information for Nuclear scientist like Oppenheimer

  1. Mar 18, 2015 #1
    Did they read the recent physics papers about the atoms? Overall what sources of information did the old Manhatten Project Scientist like Edward Teller and Robert Oppenheimer use? I bet they must have really enjoyed what they did to be so good at it.
  2. jcsd
  3. Mar 19, 2015 #2

    Quantum Defect

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    There is a very good book about E. O Lawrence and Robert Oppenheimer that I read in College. I believe that the title was something "unexpected" like "Lawrence and Oppenheimer." I suspect that it was this one: https://www.amazon.com/Lawrence-Opp...r0&keywords="lawrence+and+oppenheimer"+oxford

    My favorite stories in the book were about E. O. Lawrence's laboratory. He would stay at the Faculty CLub when his students were working in the laboratory. He found that if he turned on his radio, he would hear interference from the cyclotron. He would doze in his room with the radio on, and if he heard the interference cut out, he would get up and walk over to the laboratory to see what was wrong. Anyone who went to graduate school can appreciate what it must have been like in this group. Another story of Lawrence's lab was that he lost out on a Nobel because his lab had a master-switch that the researchers used to turn everything off. In some experiments, the group was actually synthesizing radioactive nuclei, but they never realized it because the "master switch" turned off the detectors at the same time that they turned off the means for producing the nuclei. Here's a quote from one of the workers at the RadLab:
    "We looked pretty silly. We could have made the discovery at any time."
    Robert Thorton, a Rad Lab physicist,
    on artificial radioactivity.

    Oppenheimer was involved in a lot of the very early work in quantum mechanics. In physical chemistry the thing that he is most famous for is the "Born-Oppenheimer" approximation (a separation of nuclear and electronic motion). It underlies much of what you learn in physical chemistry about the quantum behavior of atoms, molecules and chemical reactions. When I was in college, I watched a very good miniseries documentary on Oppenheimer's life and his work on the bomb made by the BBC. It starred Sam Waterson as Oppenheimer. http://www.barnesandnoble.com/w/dvd-oppenheimer-sam-waterston/6854147?ean=883929017904
  4. Mar 19, 2015 #3


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    Well, what research have you done to answer your own question?

    Your question is somewhat unclear.

    "Overall what sources of information did the old Manhatten (sic) Project Scientist like Edward Teller and Robert Oppenheimer use?"

    Are you talking about when the Project was working to develop an atomic bomb? Before? After?

    There are a number of articles available on the web concerning the Manhattan Project and the development of nuclear weapons. Richard Rhodes wrote two books dealing with this topic (out of four altogether), the first of which, on the development of the atomic bomb, earned him a Pulitzer Prize. These are just two examples; many more books on nuclear weapons development have been written since 1945, although the earliest books contain few technical details because these were still classified at the time.

    If you read even brief biographies of these two men, you'll find that up until they joined the project, they were still working scientists.



    Since no one had ever tried to develop a nuclear bomb before, and because the field was so new, O and T didn't have the luxury of reading about it in the literature. There was a lot of original research which had to be done before the physics of a bomb was understood well enough to design one. :wink:
  5. Dec 20, 2016 #4
    Of course they enjoyed the research. Their emotional reaction to the bomb itself depended on which scientist.

    They already had lots of background knowledge in physics through their own education and research. Leading up to the Manhattan project they read journal articles and had discussions with the relatively small group of nuclear scientists. They went to the major scientific conferences. It was a rather exclusive club and they all knew each other.

    They knew that by smashing the atom it was possible to release tremendous energies. The problem was to initiate and control this process.

    The critical breakthrough relating to the bomb was in 1939 when Hahn and Strassmann revealed they had split the uranium atom resulting in a tremendous release of energy. In simple terms the atoms it split up into had less total mass than the original uranium atom and the rest came out as energy as explained by the mass-energy equivalence E=mc2. Hahn and Strassmann published their findings in early 1939. A slow neutron could trigger this reaction.

    Fermi found out that on average two neutrons were released per reaction. So in goes one neutron, out comes two neutrons and lots of energy. This raises the possibility of a self-sustaining chain reaction under the right circumstances. If this happens slowly, you get heat which you can use to boil water. If this happens fast enough, lots of energy is released in a very short amount of time; in other words it explodes.

    Experiments and calculations by many people revealed more details such as why our planet doesn't blow up. More than 99% of natural uranium is U238 and they figured out that the excitation energy due to an added slow neutron was less than the critical energy. For U235 the opposite is true. So they knew the key ingredient was U235. You just needed to separate enough U235.

    Of course this is only very basic knowledge, and they still had lots of work to do both on the science and engineering side, and also to procure the needed amount of U235 among other things. The Manhattan Project started in 1939 and the first bomb was not tested until 1945.

    I think the Wendestein 7-X project is far more interesting than this topic. Unfortunately, it's much harder to create a practical nuclear fusion reactor to supply safe energy to the world than to blow things up.
    Last edited: Dec 20, 2016
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