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Homework Help: Decay of a roe meson

  1. Jan 19, 2005 #1
    I just started a class in particle physics this semester, and I really need help on one of our first homework problems. We are supposed to show that while the following decays are allowed:

    roe(+) --> pi(0)pi(+)
    roe(-) --> pi(0)pi(-)
    roe(0) --> pi(+)pi(-)

    the following decay is not allowed:

    roe(0) --> pi(0)pi(0)

    I am pretty sure the reason is that it violates a conservation law, but I don't know which one. We have barely touched on what quantities are conserved in lecture. I can see that charge is conserved in all cases, so no problem there.

    We are also told that the roe meson is a spin 1 particle, so I think that should play a role. However, the part of quantum mechanics that dealt with angular momentum and spin was a bit treacherous for me. Any help is greatly appreciated.
  2. jcsd
  3. Jan 19, 2005 #2


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    This all sounds pretty fishy to me.... Oh perhaps you mean [itex] \rho [/itex] that is rho!

    You might benifit by reading This thread.
  4. Jan 19, 2005 #3
    Fantastic! I am already familiar with LaTex.
  5. Jan 19, 2005 #4
    For anyone reading this thread, that link was just about using LaTex for math symbols...I still REALLY need help with this problem!!!

  6. Jan 19, 2005 #5
    I'm not an expert in particle physics, but have you checked

    1.) spin
    2.) parity

    I think rho mesons have both their quark and antiquark aligned, whereas pions have them antiparallel so one rho can't make two pions.
  7. Jan 19, 2005 #6
    From what I have deduced, I think the culprit is parity. Could you explain what you know about parity? I have always found it a mysterious concept.
  8. Jan 19, 2005 #7


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