Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Half-spin baryons with identicle quarks?

  1. Jul 30, 2012 #1
    Do any 1/2 spin baryons exist that are made of three identical (flavored) quarks? I know the Δ-, Δ++ and Ω- have 3/2 spin. If the 1/2 spin versions of these particles can't exist, then why not?
  2. jcsd
  3. Jul 30, 2012 #2
    The color wave function is totally antisymmetric, the flavor is totally symmetric, so that the spin has to be totally symmetric.
  4. Jul 30, 2012 #3


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Spin of a composite particle is best identified with the total angular momentum J = L + S, where L and S are the "orbital" and spin angular momentum of the constituents. There are indeed spin 1/2 versions of the ##\Delta## particles, which are in different orbital angular momentum states compared to the lightest ##\Delta##. A list can be found here: http://pdglive.lbl.gov/listing.brl?fsizein=1&exp=Y&group=BXXX020 [Broken]. The known ##\Omega## states are listed at http://pdglive.lbl.gov/listing.brl?fsizein=1&exp=Y&group=BXXX035 [Broken]. It doesn't appear that their angular momentum has been well measured. Presumably they are too short-lived, or their decays too dirty to make this easy, but I am no experimentalist.
    Last edited by a moderator: May 6, 2017
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook