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Is Λ the ∑ particle? or is Λ the Δ particle? notation clarification

  1. May 17, 2014 #1
    ive noticed some problems have the quark composition of Λ as uds, but in the Baryon Octuplet that is the same composition as ∑. I always thought Λ was another way of writing Δ, so the quark composition would be ddu, am I wrong?
  2. jcsd
  3. May 17, 2014 #2
    Yes, you are wrong, Λ (Lambda) and Δ (Delta) are different greek letters and different particles.
  4. May 17, 2014 #3

    Vanadium 50

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    Yes, you are wrong. The Lambda and the Delta are different particles with different symbols. The bottom line of the triangle is significant. The neutral Sigma and Lambda have the same quark content, but are still different particles, just as C2H6O can be either ethanol or dimethyl ether.
  5. May 17, 2014 #4
    Thanks for clearing that up, much appreciated.
  6. May 20, 2014 #5


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    The u and d quarks in the Lambda are in a spin zero state.
    The u and d quarks in the Sigma0 are in a spin one state.
  7. May 20, 2014 #6


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    They are excitations of the same quark content bound state...Just as Δ+ is an excitation of the proton...
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