The discussion revolves around the constituents of nucleons, specifically focusing on the types of virtual quarks present within protons and neutrons. Participants explore whether only up and down quarks are involved or if heavier quarks can also contribute, considering both theoretical and experimental perspectives.
Participants express a range of views regarding the presence of heavier quarks in nucleons, with no consensus reached on whether they are significantly present or how to accurately measure their contributions.
Participants note the limitations of current experimental methods and the challenges in distinguishing between pre-existing and collision-generated quarks, highlighting the dependence on specific experimental conditions and the need for high-accuracy measurements.
mathman said:I understand that nucleons (protons and neutrons) consist of 3 valence quarks and a sea of other stuff, virtual quark-antiquark pairs and gluons. Question: are the virtual quarks only up and down or may there be heavier quarks?
fzero said:All flavors contribute because of g\leftrightarrow q\bar{q} processes. A quick search didn't turn up any sort of canonical reference, but http://cerncourier.com/cws/article/cern/29441 explains some experimental measurements related to the strange component of the proton.
My confusion is how do you tell what was there already as compared to what happens when protons collide with something.Bill_K said:Naturally if you hit a proton hard enough, heavy quarks will be produced. I thought your question was, is there a significant percentage of heavy quarks already in the proton. And to answer this, as described in the ref, you want to do low energy experiments with high accuracy.