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Dressed-quark anomalous magnetic moments
Lei Chang1, Yu-Xin Liu, Craig D Roberts
1Institute of Applied Physics and Computational Mathematics, Beijing, China.
Physical Review Letters
|March 17, 2011
Summary
Dynamical chiral symmetry breaking generates a large, momentum-dependent anomalous chromomagnetic moment for light quarks. This nonperturbative effect also results in a similar-magnitude, opposite-sign anomalous electromagnetic moment for these quarks.
Area of Science:
- Quantum Chromodynamics (QCD)
- Particle Physics
- Theoretical Physics
Background:
- Perturbation theory suggests massless fermions lack magnetic moments.
- Understanding quark properties is crucial in high-energy physics.
Purpose of the Study:
- To explain the generation of anomalous magnetic moments in light quarks.
- To investigate the role of nonperturbative QCD phenomena.
Main Methods:
- Analysis of dynamical chiral symmetry breaking.
- Theoretical investigation of quark properties at infrared momenta.
Main Results:
- Identified a momentum-dependent anomalous chromomagnetic moment for dressed light quarks.
- Demonstrated the generation of an anomalous electromagnetic moment with similar magnitude and opposite sign.
Conclusions:
- Nonperturbative effects in QCD can lead to measurable magnetic moments in quarks.
- Dynamical chiral symmetry breaking is key to understanding these anomalous moments.
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