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Foundations of Physics

, Volume 30, Issue 4, pp 577–597 | Cite as

An Effective Field Theory Model to Describe Nuclear Matter in Heavy-Ion Collisions

  • M. M. Islam
  • H. Weigel
Article

Abstract

Relativistic mean field theory with mesons σ, ω, π and ρ mediating interactions and nucleons as basic fermions has been very successful in describing nuclear matter and finite nuclei. However, in heavy-ion collisions, where the c. m. energy of two colliding nucleons will be in the hundreds of GeV region, nucleons are not expected to behave as point-like particles. Analyses of elastic pp and ¯pp scattering data in the relevant c. m. energy range show that the nucleon is a composite object—a topological soliton or Skyrmion embedded in a condensed quark-antiquark ground state. Against this backdrop, we formulate an effective field theory model of nuclear matter based on the gauged linear σ-model where quarks are the basic fermions, but the mesons still mediate the interactions. The model describes the nucleon as a Skyrmion and produces a q¯q ground state analogous to a superconducting ground state. Quarks are quasi-particles in this ground state. When the temperature exceeds a critical value, the scalar field in the ground state vanishes, quarks become massless, and a chiral phase transition occurs leading to chiral symmetry restoration. We explore the possibility of a first order phase transition in this model by introducing suitable self-interactions of the scalar field. Internal structures of the Skyrmions are ignored, and they are treated as point-like fermions.

Keywords

Soliton Scalar Field Nuclear Matter Chiral Symmetry Order Phase Transition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Publishing Corporation 2000

Authors and Affiliations

  • M. M. Islam
    • 1
  • H. Weigel
    • 2
  1. 1.Department of PhysicsUniversity of ConnecticutStorrs
  2. 2.Center for Theoretical Physics, Laboratory of Nuclear Science and Department of PhysicsMassachusetts Institute of TechnologyCambridge

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