Color conservation in gluon fragmentation

Click For Summary
SUMMARY

The discussion centers on color conservation during gluon fragmentation into quark-antiquark pairs, specifically focusing on the charm quark (c) and its antiparticle (c_bar). Gluons, which carry both a color and an anticolor, can fragment into colored quarks while maintaining overall color neutrality through connections to other colored objects in the hadron. The conversation emphasizes that at every vertex in quantum chromodynamics (QCD) processes, color must be conserved, and the surrounding hadron plays a crucial role in this conservation. A proposed method for visualizing this process involves using Feynman diagrams to represent gluons as double lines that indicate both color and anticolor charges.

PREREQUISITES
  • Understanding of quantum chromodynamics (QCD)
  • Familiarity with Feynman diagrams
  • Knowledge of color charge in particle physics
  • Basic concepts of quark-antiquark pair production
NEXT STEPS
  • Study the role of gluons in QCD processes
  • Learn about color charge conservation in particle interactions
  • Explore Feynman diagrams and their applications in particle physics
  • Investigate the fragmentation process of quarks and gluons
USEFUL FOR

Particle physicists, students of quantum chromodynamics, and anyone interested in the mechanisms of color charge conservation in high-energy physics.

Manojg
Messages
47
Reaction score
0
Hi,

When a gluon fragments to a quark anti-quark pair (c c_bar for an example), how is color conserved? Gluon is colored but c c_bar pair is colorless.

Thanks.
 
Physics news on Phys.org
Gluons carry both a color and an anticolor. A gluon that was red anti-green for example could fragment into a red quark and a green antiquark.
 
Bill_K said:
Gluons carry both a color and an anticolor. A gluon that was red anti-green for example could fragment into a red quark and a green antiquark.

which, since they have different color/anticolor does not form a color neutral state.
 
When the q-qbar pair fragments to hadrons, there will be a color connection to the other colored objects in the hadron that contained the original gluon.
 
Bill_K said:
Gluons carry both a color and an anticolor. A gluon that was red anti-green for example could fragment into a red quark and a green antiquark.

Yes, but we are taking about quark and its own anti-quark like c and c_bar. If c is red, c_bar must be anti-red.
 
Vanadium 50 said:
When the q-qbar pair fragments to hadrons, there will be a color connection to the other colored objects in the hadron that contained the original gluon.

Fine, but at every vetex, color (and other like charge) should be conserved, isn't it? So, at vertex where gluon fragments to c and c_bar, color should be conserved.
 
Manojg said:
Yes, but we are taking about quark and its own anti-quark like c and c_bar. If c is red, c_bar must be anti-red.


No, if the gluon splits up into a red c, the c_bar cannot be anti-red; as far as I understand.
 
Yes, but you are starting with a colored state, ignoring the rest of the hadron that gave you the gluon. It's that rest of the hadron that solves your problem. You can't ignore it.
 
There is a nice way to represent gluons and color charge conservation in QCD processes.

In a Feynman diagram replace every gluon with a double line, i.e. two antiparallel lines running into opposite direction and carrying a color charge and an anti-color charge, respectively.

http://www.hindawi.com/journals/ahep/2010/floats/723105/thumbnails/723105.fig.002_th.jpg
 

Similar threads

High School Do Alternative Explanations for Gluons Exist and How Can We Test Them?
  • · Replies 38 ·
2
Replies
38
Views
5K
Undergrad Color state of quarks in quark-gluon plasma
  • · Replies 2 ·
Replies
2
Views
2K
Undergrad What happens to a gluon that does not have enough energy to hadronize?
  • · Replies 9 ·
Replies
9
Views
3K
Undergrad Are Hadrons and Gluons Symmetric Against Interchange of Colours?
  • · Replies 8 ·
Replies
8
Views
3K
Undergrad Understanding Gluon Self-Interaction and Quark/Gluon Jet Differentiation
  • · Replies 9 ·
Replies
9
Views
2K
Graduate How Does the ss¯ Pair Affect the Partial Width Γ2 in Gluon Decays?
  • · Replies 4 ·
Replies
4
Views
3K
Undergrad No "i" in the Triple gluon vertex Feynman Rule
  • · Replies 8 ·
Replies
8
Views
2K
High School Quark Gluon Plasma In the Presence of Charged Leptons?
  • · Replies 4 ·
Replies
4
Views
2K
High School Gluon Color: Possessing 2 Eigenvalues & Relationship to Tao
  • · Replies 16 ·
Replies
16
Views
3K
Graduate Color confinement in high-energy quark knockout
  • · Replies 3 ·
Replies
3
Views
2K