BARYONS AS CHIRAL SOLITONS IN THE NAMBU-JONA-LASINIO MODEL

Citation
R. Alkofer et al., BARYONS AS CHIRAL SOLITONS IN THE NAMBU-JONA-LASINIO MODEL, Physics reports, 265(3), 1996, pp. 140-252
Citations number
156
Categorie Soggetti
Physics
Journal title
ISSN journal
03701573
Volume
265
Issue
3
Year of publication
1996
Pages
140 - 252
Database
ISI
SICI code
0370-1573(1996)265:3<140:BACSIT>2.0.ZU;2-G
Abstract
The description of baryons as chiral solitons of the Nambu-Jona-Lasini o (NJL) model is reviewed. A motivation for the soliton description of baryons is provided from large N-C QCD. Rigorous results on the spont aneous breaking of chiral symmetry in QCD are discussed. It is then ar gued that the NJL model provides a fair description of low-energy hadr on physics. The NJL model is therefore employed to mimic the low-energ y chiral flavor dynamics of QCD. The model is bosonized by functional integral techniques and the physical content of the emerging effective meson theory is discussed. In particular, its relation to the Skyrme model is established. The static soliton solutions of-the bosonized NJ L model are found, their properties discussed, and the influence of va rious meson fields studied. These considerations provide strong suppor t of Witten's conjecture that baryons can be understood as soliton sol utions of effective meson theories. The chiral soliton of the NJL mode l is then quantized in a semiclassical fashion and various static prop erties of the nucleon are studied. The dominating 1/N-C corrections to the semiclassically quantized soliton are investigated. Time-dependen t meson fluctuations off the chiral soliton are explored and employed to estimate the quantum corrections to the soliton mass. Finally, hype rons are described as chiral solitons of the NJL model. This is done i n both, the Collective rotational approach of Yabu and Ando as well as in the bound state approach of Callan and Klebanov.