Institut für Theoretische Physik
Point-Form and Instant-Form Calculations of Electromagnetic Form Factors K. Berger , W. Plessas , and R.F. Wagenbrunn
[email protected]
¨ Graz, Universitatsplatz ¨ Institut fur ¨ Theoretische Physik, Universitat 5, A-8010 Graz, Austria
Mini-Workshop Bled: Effective Quark-Quark Interaction Bled, Slovenia, 07.07.–14.07.2003
Institut für Theoretische Physik
Contents of the Talk
K. Berger
–
Point-Form and Instant-Form Calculations of Electromagnetic Form Factors
Hamiltonians of the CQMs
Covariant Results for Electroweak Nucleon Form Factors
Electromagnetic Baryon Structure: Results from CQMs
Electric Radii and Magnetic Moments of Light and Strange Baryons
Relativistic Quantum Mechanics: operators fulfill Poincaré invariance
Forms of Relativistic Quantum Mechanics (Dirac)
Mass Operator
Bakamjian-Thomas Construction in Point Form
Bakamjian-Thomas Construction in Instant Form
Eigenvalue Problem of Mass Operator
Representation of States in Point Form and Instant Form
Formalism of Relativistic Calculations
Invariant Form Factors
Institut für Theoretische Physik
Contents of the Talk
Spectator Approximation for current operators K. Berger
–
Point-Form and Instant-Form Calculations of Electromagnetic Form Factors
Quantitative Comparison of Point Form and Instant Form Results for 2-Body System
Institut für Theoretische Physik
Contents of the Talk
Results for Nucleons
Conclusions
K. Berger
–
Point-Form and Instant-Form Calculations of Electromagnetic Form Factors
GBE Constituent Quark Model
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The quark-quark interaction consists of a linear confinement
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and of the spin-spin component of the hyperfine interaction
The eigenvalue problem for is solved by the stochastic variational method leading to three-quark eigenstates . E
Institut für Theoretische Physik
Three-quark Hamiltonian of the Goldstone-boson-exchange (GBE) CQM [L.Ya. Glozman et al., Phys. Rev. D 58 (1998) 094030]
K. Berger
–
Point-Form and Instant-Form Calculations of Electromagnetic Form Factors
OGE Constituent Quark Model Three-quark Hamiltonian of the one-gluon-exchange (OGE) CQM:
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9
