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Radio-Active Cryo-Physics

  1. Oct 30, 2005 #1
    How does near absolute zero temperatures effect Radio active Materials?

    Does Radioactive decay of a Radio Active Isotope slow down as the material approaches absolute zero temperature?:smile:
  2. jcsd
  3. Oct 30, 2005 #2
    I wondered about this once myself, and although I am not sure of what really happens, I reasoned to myself that since the decay equation is temperature independent, there would be no effect on the decay with cooling. Also, decay is a result of the neutron and proton ratio within the atom, temperature is influences how atoms interact with each other. However, cooling a material so low seems it ought to have some effects on the material properties which may be an influence to decay, that is why I am unsure of my answer.
    Last edited: Oct 30, 2005
  4. Oct 31, 2005 #3


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    The temperature is a manifestation (the way we measure) atomic motion - the hotter an object, the faster the atoms in a solid or liquid vibrate or diffuse, or in a gas, the faster they move in the gas (and the higher the pressure in a given volume).

    The behavior of the nucleus of a radionuclide is independent of the motion of an atom.

    Of course, if one were to cause an collection of radioactive atoms to travel at relativistic speeds, the radionuclide(s) would appear to have a different half-life (time dilation).
    Last edited: Oct 31, 2005
  5. Nov 2, 2005 #4


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    Although temperature is directly proportional to kinetic energy, it is not really just a measure of vibration or movement in atoms. I have seen no real equations for temperature, except i derived this one from kinetic energy formula's,

    T = ( 1/3 mv^2 ) / ( K )

    where K is boltzmann's constant = 1.38066*10^-23 J/K
    m is mass and v is velocity
    The mass and boltzmann's constant can be cancelled down if you subsitute in variables such as the mole, however the equation contains more variables at that point.
    Last edited: Nov 2, 2005
  6. Nov 2, 2005 #5
    Is there a radio Active Isotope that, Especially a Beta Emitter that can be effectively slowed in its Beta decay process, Like P40 which has a half life of 260ms with 100% beta emission, If we can effectively slow and control Beta emitters then we can use Beta emitters as a fuel source for harvesting emitted electrons.

    Question. In theory, Can there be a Radio Active Isotope that (acts) like a BEC or Bose-Einstein condensate when using Cryo-Physics?

    If we could effectively slow down or speed up a beta decay process on the fly using BEC concepts.

    This way the fuel will last as long as we want it to.

    Controlling a Hard Beta emitter would bring new sources of harvestable energy for Space travel and such.

    If this is possible then using specialized Capacitors to capture Beta emissions internally could be a promising persuit. Self charging Capacitors would be wild.
    Last edited: Nov 2, 2005
  7. Nov 2, 2005 #6


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    Try these -


  8. Nov 2, 2005 #7


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    There are a few problems with this scenario.

    With a short half-life (e.g. 260 ms), the radionuclide would decay very rapidly, so that the activiy would drop by 3 orders of magnitude in 10 half-lives (here 2600 sec < 1 hr), by 6 orders of magnitude in 20 half-lives, and by 9 orders of magnitude in 30 half-lives.

    The specific energy is very low. Consider the beta energy as compared to the mass of the nucleus, and consider that the beta energy has a spectrum (the anti-neutrino shares some of the decay energy), and the most probable energy is about 1/3 of the max energy.

    Beta particles are emitted in all directions. To establish a sufficient potential, a good collection system is required.

    I recommend some homework on BEC - http://en.wikipedia.org/wiki/Bose-Einstein_Condensate
    The nuclear properties are not affected by the condensation of atoms.

    and - http://hyperphysics.phy-astr.gsu.edu/hbase/particles/spinc.html#c4
  9. Nov 2, 2005 #8
    Could a (tuned) Cooling LASER effectively penatrate an Electron Shell to Cool a Nucleus within the Atom or is this another dead end?

    Are there any loop holes to take advantage of?
  10. Nov 2, 2005 #9


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    Lasers would not work either.

    To affect the nucleus would require a high energy gamma-ray (photo-neutron reaction) > 1.6 MeV (gamma energy depends on the target radionuclide), a high energy charged particle (p, alpha, or otherwise) of several MeV, or neutrons (thermal energies or otherwise), which could be obtained in a conventional nuclear reactor.
  11. Nov 3, 2005 #10

    Can Magnetic field lines effectly penetrate an Electron Shell to the Nucleus?

    Magnetic Cooling?

    Last ditch effort to find a means.
  12. Nov 4, 2005 #11


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    Magnetic cooling is primarily done on ATOMS, not nucleus. Trying to "cool" a nucleus is actually a rather meaningless concept, since "heat" and "temperature" normally requires a statistics of large number of particles. So cooling the nucleons within a nucleus is a rather vague concept.

    Secondly, the nucleus does see external magnetic field. This is how NMR works. But it is the whole nucleus as a whole that reacts to this. You can't use the magnetic field to individually "cool" or manipulate the individual nucleons or partons inside the nucleus - at least we don't know anything that can do this.

  13. Nov 4, 2005 #12
    I think if we had Coherent Magnetism both Bipolar and Monopolar then with some additional precision electronics we could interfere with the nucleons on a more advanced level.

    But I do not know if Coherent Magnetism exists?, Let alone advancements in Monopolar coherent magnetic fields.:smile:

    Hopefully it's something the future of science can figure out.

    Being able to control (all forms) of Radio Active decay rate would give us a super sharp edge on energy.:rofl:
  14. Nov 4, 2005 #13


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    Even in NMR, the externally applied magnetic field is insufficient to align the nuclear
    magnetic moments.

    What the externally applied magnetic field does is align the moments of the electrons
    surrounding the nucleas. It is then the influence of these aligned electrons that actually
    aligns the magnetic moment of the nucleus.

    Dr. Gregory Greenman
  15. Nov 4, 2005 #14


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    But how do you explain the fact that you do get to probe the nucleus of hydrogen, for example, where the resonance freq. happen to match what you would expect for a bare nucleus. I'm not saying there's no shielding, but in pulse NMR, for example, the RF field that you apply to flip the spins will only flip the nuclear spins, and not the electrons.

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