Extension of the Nambu-Jona-Lasinio model predictions at high densities and temperatures using an implicit regularization scheme
- Departamento de Fisica Teorica, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ 20559-900 (Brazil)
- Departamento de Ciencias Exatas, Universidade Federal de Lavras, Cx. Postal 37, 37200-000, Lavras, MG (Brazil)
- Instituto de Fisica Teorica, Universidade Estadual Paulista, Rua Pamplona 145, Sao Paulo, SP 01405-900 (Brazil)
- CBPF, Centro Brasileiro de Pesquisas Fisicas Rua Xavier Sigaud 150, 22290-180 Urca Rio de Janeiro, RJ (Brazil)
Traditional cutoff regularization schemes of the Nambu-Jona-Lasinio model limit the applicability of the model to energy-momentum scales much below the value of the regularizing cutoff. In particular, the model cannot be used to study quark matter with Fermi momenta larger than the cutoff. In the present work, an extension of the model to high temperatures and densities recently proposed by Casalbuoni, Gatto, Nardulli, and Ruggieri is used in connection with an implicit regularization scheme. This is done by making use of scaling relations of the divergent one-loop integrals that relate these integrals at different energy-momentum scales. Fixing the pion decay constant at the chiral symmetry breaking scale in the vacuum, the scaling relations predict a running coupling constant that decreases as the regularization scale increases, implementing in a schematic way the property of asymptotic freedom of quantum chromodynamics. If the regularization scale is allowed to increase with density and temperature, the coupling will decrease with density and temperature, extending in this way the applicability of the model to high densities and temperatures. These results are obtained without specifying an explicit regularization. As an illustration of the formalism, numerical results are obtained for the finite density and finite temperature quark condensate and applied to the problem of color superconductivity at high quark densities and finite temperature.
- OSTI ID:
- 21191971
- Journal Information:
- Physical Review. C, Nuclear Physics, Vol. 77, Issue 6; Other Information: DOI: 10.1103/PhysRevC.77.065201; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
- Country of Publication:
- United States
- Language:
- English
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