The large-N{sub c} renormalization group
- University Coll. of Swansea (United Kingdom). Dept. of Physics
- Los Alamos National Lab., NM (United States)
In this talk, we review how effective theories of mesons and baryons become exactly soluble in the large-N{sub c}, limit. We start with a generic hadron Lagrangian constrained only by certain well-known large-N{sub c}, selection rules. The bare vertices of the theory are dressed by an infinite class of UV divergent Feynman diagrams at leading order in 1/N{sub c}. We show how all these leading-order dia, grams can be summed exactly using semiclassical techniques. The saddle-point field configuration is reminiscent of the chiral bag: hedgehog pions outside a sphere of radius {Lambda}{sup {minus}1} ({Lambda} being the UV cutoff of the effective theory) matched onto nucleon degrees of freedom for r {le} {Lambda}{sup {minus}1}. The effect of this pion cloud is to renormalize the bare nucleon mass, nucleon-{Delta} hyperfine mass splitting, and Yukawa couplings of the theory. The corresponding large-N{sub c}, renormalization group equations for these parameters are presented, and solved explicitly in a series of simple models. We explain under what conditions the Skyrmion emerges as a UV fixed-point of the RG flow as {Lambda} {yields} {infinity}.
- Research Organization:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States); University Coll. of Swansea (United Kingdom). Dept. of Physics
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 100310
- Report Number(s):
- LA-UR-95-1490; CONF-950293-2; ON: DE95011992; TRN: 95:020262
- Resource Relation:
- Conference: Nuclear and particle physics conference, Seoul (Korea, Republic of), 6-10 Feb 1995; Other Information: PBD: [1995]
- Country of Publication:
- United States
- Language:
- English
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