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Muon Spectroscopy

  1. Mar 8, 2005 #1
    I've been doing some research on Muon spectroscopy, and am not that far in the physics world yet. I've got kind of a fuzzy picture of what goes on, but could use some help in identifying some key concepts. The information I have been getting is from the following paper

    Muon-Spin Rotation Studies of Electronic Properties of Molecular Conductors and Superconductors

    Stephen J. Blundell

    Department of Physics, Oxford University, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom

    Received March 16, 2004

    which I recieved from the American Chemical Society Data Base

    What I have found thus far is that 100% polarized muons can be fired at a sample under study, and that the magnetic environment at the time of muon decay can have an effect on the emittance of positrons. Of prime importance to the theory of this form of study is the

    Now my understanding is that since the muon has negative helicity, the spin axis points antiparallel to the direction of motion. Why does precession occur? Can anyone help clairify this or suggest a good resource?

    Last edited by a moderator: Mar 8, 2005
  2. jcsd
  3. Mar 8, 2005 #2


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    The precession occurs because the muon spin is not along the direction of the external magnetic field that the muon is in. This is why, if the muon decays too quickly to "sample" the surrounding field, it will not have time to precess.

    However, in most cases, the muon lifetime is long enough (some people think it is too long and that's why neutron scattering is used in the study of many other materials) that the muon spectrum in a typical muSR spectroscopy will provide more of an "average" information of the magnetic orientation of the material being studied.

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