Electroweak amplitudes in chiral quark models
Description
After referring to some basic features of chiral models for baryons, with quarks and mesons, we describe how to construct model states representing physical baryons. We consider soliton models such as the Linear Sigma Model or the Chromodielectric Model, and bag models such as the Cloudy Bag Model. These models are solved approximately using variational approaches whose starting point is a mean-field description. We go beyond the mean-field description by introducing quantum fluctuations in the mesonic degrees of freedom. This is achieved, in a first step by using a quantum state to represent meson clouds and, secondly, by performing an angular momentum and isospin projection from the mean-field state (actually a coherent state). Model states for baryons (nucleon, Delta, Roper) constructed in this way are used to determine several physical properties. In this seminar we paid a particular attention to the nucleon-delta electromagnetic and weak transition, presenting the model predictions for the electromagnetic and axial amplitudes. (author)
Additional details
Publishing Information
- Publisher
- AIP
- Imprint Place
- New York (United States)
- ISBN
- 0-7354-0223-X
- Imprint Title
- Proceedings of the 9. Hadron physics; 7. Relativistic aspects of nuclear physics. A joint meeting on QCD and QGP
- Imprint Pagination
- 757 p.
- Journal Page Range
- p. 241-255
Conference
- Title
- 9. Hadron physics; 7. Relativistic aspects of nuclear physics
- Dates
- 28 Mar - 3 Apr 2004
- Place
- Angra dos Reis, RJ (Brazil)
INIS
- Country of Publication
- United States
- Country of Input or Organization
- Brazil
- INIS RN
- 37050367
- Subject category
- S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS;
- Resource subtype / Literary indicator
- Conference, Numerical Data
- Descriptors DEI
- AMPLITUDES; BAG MODEL; CHIRAL SYMMETRY; DELTA BARYONS; ELECTROMAGNETIC FORM FACTORS; ELECTROPRODUCTION; ISOSPIN; MEAN-FIELD THEORY; MESONS; N-1440 BARYONS; NUCLEONS; NUMERICAL DATA; QUARKS; SIGMA MODEL; UNIFIED-FIELD THEORIES
- Descriptors DEC
- BARYONS; BASIC INTERACTIONS; BOSON-EXCHANGE MODELS; BOSONS; COMPOSITE MODELS; DATA; DIMENSIONLESS NUMBERS; ELECTROMAGNETIC INTERACTIONS; ELEMENTARY PARTICLES; EXTENDED PARTICLE MODEL; FERMIONS; FIELD THEORIES; FORM FACTORS; HADRONS; INFORMATION; INTERACTIONS; MATHEMATICAL MODELS; N BARYONS; N*BARYONS; PARTICLE INTERACTIONS; PARTICLE MODELS; PARTICLE PRODUCTION; PARTICLE PROPERTIES; PERIPHERAL MODELS; QUARK MODEL; SYMMETRY
Optional Information
- Notes
- 41 refs., 10 figs.