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Difference between J/Psi and its excited states

  1. May 20, 2013 #1
    The J/Psi is a state of charmonium with J=1, S=1, L=0. So [itex]J^{PC} = 1^{--}[/itex].
    It can be excited to states [itex]J^\prime \textrm{ and } J^{\prime\prime}[/itex], but these don't change any of these numbers. So what is changing?
  2. jcsd
  3. May 20, 2013 #2


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    The "charmonium" page in Wikipedia has a full list of the charmonium states and their quantum numbers. By J' and J'' do you mean ψ(3686) and ψ(3770)? These are the lowest lying states with JPC = 1--. Looks like the first one is a radial excitation, n = 2, and the second one has L = 2.
  4. May 23, 2013 #3
    I did, thanks! I wasn't aware that radial excitation was possible without changing the name of the particle.
  5. May 23, 2013 #4


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    Staff: Mentor

    If the energy (or any other particle property) is different, the particle has a different name - sometimes, it is just an additional prime, a star or a number (denoting the approximate mass), but the name is different.
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