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Could lone subatomic particles be stabilised if placed in larger molecules?

  1. May 10, 2012 #1
    Could lone subatomic particles be "stabilised" if placed in larger molecules?

    My main area is molecular biology and biochemistry, but I've had a growing interest in particle physics for a while. Could lone subatomic particles be "stabilised" if they were placed inside of a larger molecule?

    For example, is there a reason why a Mg atom at the center of a chlorophyll molecule's chlorin ring, or the Co atom coordinated in cobalamin, can't be replaced with a delta baryon of +2 charge? (The Mg and Co are +2 as well in those molecules)

    Could positrons be stored inside of a fullerene molecule (a sphere made entirely of carbon rings?) If the walls are all organic and uncharged, shouldn't they repel the positively charged positron towards the center?

    Could this be a possible viable way to capture and store exotic subatomic particles?
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  3. May 10, 2012 #2

    Vanadium 50

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    Re: Could lone subatomic particles be "stabilised" if placed in larger molecules?

    No, the particles would still decay at their normal rate.
  4. May 10, 2012 #3


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    Re: Could lone subatomic particles be "stabilised" if placed in larger molecules?

    Unstable particles are unstable because they decay without any other particles - it does not matter where you try to store them, they still decay, even in a perfect vacuum.
    There are some cases where this can be wrong, especially in neutron stars. But this is something you don't get on earth.

    Positrons are stable - if you don't let them reach any electrons, they survive. However, your molecules have a lot of electrons, so they are not suitable to contain positrons.
  5. May 10, 2012 #4
    Re: Could lone subatomic particles be "stabilised" if placed in larger molecules?

    Lone subatomic particles do decay at their normal rate, with one exception. Muons, with a 2.2 microsecond half life, have been stored in a storage ring at a relativistic gamma of about 29.3, which due to time dilation, stretched the observed half life in the Lab to about 64 microseconds (standard time dilation).

    Beryllium-7 (not a subatomic particle) is radioactive, with a half life of about 53 days, and decays only by capturing an atomic electron from the k shell. beryllium-7 nuclei (stripped of electrons) are stable when stored in a storage ring. Also, some Japanese researchers have been able to change the half life of Be7 atoms by a small amount by putting it into different chemical environments. See http://www.nature.com/news/2004/040913/full/news040913-24.html

    Finally, a neutron, a radioactive elementary particle, is stable when combined with protons in nuclei.
  6. May 12, 2012 #5


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    Re: Could lone subatomic particles be "stabilised" if placed in larger molecules?

    The basic reason this will not work is that the decay of these particles is based upon Nuclear forces in the nucleus. Simply swapping these particles in place of normal atoms does nothing to these nuclear forces.

    Each carbon atom has an electron cloud which will attract the positron. It will annihilate very quickly with one of these electrons. The carbon atoms are neutral overall at large scales, but because they are not point particles the charge isn't 100% neutral at the atomic scale. Hence you get effects such as the van der waals force.

    Bobs examples above are semi-correct. The delay in muon decays is a normal process of relativity, and will affect ANY decay of any particle if you accelerate it close to the speed of light. Note that in the frame of reference of any of these particles they do not take any longer or shorter to decay. (No one experiences time dilation in their own frame of reference. It is only when you compare two different frames that the effect occurs.)

    The Be 7 decay is a different kind of decay that also has to take into account the electrons around it, so yes, this MAY be affected by placing it in different chemical bonds. (As the link says)

    So, OVERALL the decay of subatomic particles is only affected IF it depends on the electron density around the nucleus. (Per the link) Most subatomic particles do not decay this way however.
    Last edited: May 12, 2012
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