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What is this?

  1. Sep 4, 2010 #1
    I quoted this from Hyper Physics, and I want to learn more about this, where can I? I am asking for links to places where I can learn about this ( I already know about Protons, Neutrons, Electrons and all the basic ones but now I want to get more in depth):

    Baryons are massive particles which are made up of three quarks in the standard model. This class of particles includes the proton and neutron. Other baryons are the lambda, sigma, xi, and omega particles. Baryons are distinct from mesons in that mesons are composed of only two quarks. Baryons and mesons are included in the overall class known as hadrons, the particles which interact by the strong force. Baryons are fermions, while the mesons are bosons. Besides charge and spin (1/2 for the baryons), two other quantum numbers are assigned to these particles: baryon number (B=1) and strangeness (S), which in the chart can be seen to be equal to -1 times the number of strange quarks included.

    The conservation of baryon number is an important rule for interactions and decays of baryons. No known interactions violate conservation of baryon number.

    Recent experimental evidence shows the existence of five-quark combinations which are being called pentaquarks. The pentaquark would be included in the classification of baryons, albeit an "exotic" one. The pentaquark is composed of four quarks and an antiquark, like a combination of an ordinary baryon plus a meson.
    Last edited: Sep 4, 2010
  2. jcsd
  3. Sep 4, 2010 #2


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    What exactly are you asking for here? Are you asking for sources to learn about elementary particles? Or do you want to just learn about Baryons? Or are you more interested in these "pentaquarks", which, BTW, their discovery has NOT been agreed upon yet.

    If you want to learn about the basics of elementary particles, then I would suggest the http://www.particleadventure.org/" [Broken], since you didn't describe the level of sophistication that you already have.

    BTW, don't make wholesale quote of webpages. Just provide a link, and quote ONLY the relevant part that you want to understand so that we are clear on what the issues are. The part you have quoted here covered the whole gamut of many things, which didn't make it clear what exactly is the topic that you wanted to understand.

    Last edited by a moderator: May 4, 2017
  4. Sep 4, 2010 #3


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    What is it exactly that you want to learn about? Wikipedia has some good information about baryons in general, I suppose you could use that as a starting point and also have a look at the list of references at the bottom.

    P.S. Pentaquarks are still considered hypothetical. A few experiments did seem to offer evidence of their existence, but it wasn't conclusive (i.e. could have been due to errors in the experimental setup or data analysis) and the results have not been replicated since.
  5. Sep 5, 2010 #4


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    There are 3 valence quarks in baryons. It doesn't mean there are just 3. Saying, "a proton is made up of 3 quarks" is misleading. It's composed of a whole lot of stuff.
  6. Sep 5, 2010 #5
    Like what? (prepares to have mind blown)
  7. Sep 5, 2010 #6


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    Additional quark-antiquark pairs and gluons.
  8. Sep 6, 2010 #7
    http://www.particleadventure.org/eternal-questions.html" [Broken]
    Last edited by a moderator: May 4, 2017
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