Dobado González, AntonioPeláez Sagredo, José Ramón2023-06-202023-06-201999-02-01[1] S. Weinberg, Phys. Rev. 166, 1568 (1968); Physica A 96, 327 (1979). [2] J. Gasser and H. Leutwyler, Ann. Phys. (N.Y.) 158, 142 (1984). [3] E. V. Shuryak, The QCD Vacuum, Hadrons and the Superdense Matter (World Scientific, Singapore, 1988); A. V. Smilga, Phys. Rep. 291, 1 (1997). [4] N. P. Landsman and Ch. G. van Weert, Phys. Rep. 145, 141 (1987). [5] P. Gerber and H. Leutwyler, Nucl. Phys. B321, 387 (1989). [6] M. Dey, V. L. Eletsky, and B. L. Ioffe, Phys. Lett. B 252, 620 (1990); V. L. Eletsky and B. L. Ioffe, Phys. Rev. D 47, 3083 (1993); 51, 2371 (1995); T. Hatsuda, Y. Koike, and S. H. Lee, Nucl. Phys. B394, 221 (1993). [7] G. Chanfray, M. Ericson, and J. Wambach, Phys. Lett. B 388, 673 (1996). [8] R. Dashen, S. K. Ma, and H. J. Berstein, Phys. Rev. 187, 345 [1969]. [9] L. D. Landau and E. M. Lifshitz, Statistical Physics (Pergamon, New York, 1958). [10] J. Kapusta, Finite Temperature Field Theory [Cambridge University Press, Cambridge, England, 1989]. [11] C. Riggenbach, J. F. Donoghue, J. Gasser, and B. Holstein, Phys. Rev. D 43, 127 [1991]. [12] A. Dobado and J. R. Pela´ez, Phys. Rev. D 47, 4883 (1993); 56, 3057 (1997). [13] J. A. Oller, E. Oset, and J. R. Pela´ez, Phys. Rev. Lett. 80, 3452 (1998); hep-ph/9804209. [14] F. Wilczek, Int. J. Mod. Phys. A 7, 3911 (1992). [15] H. Leutwyler, Phys. Lett. B 284, 106 (1992).0556-2821https://hdl.handle.net/20.500.14352/58726©1998 The American Physical Society. The research was supported by the Department of Energy under Contract No. DE-AC03-76SF00515. J.R.P. would like to thank the Theory Group at SLAC for their kind hospitality and the Spanish Ministerio de Educación y Cultura for financial support. This work has been partially supported by the Spanish CICYT under Contract No. AEN97-1693.In this work we study the thermodynamic properties of the pion gas starting from the realistic elastic scattering phase shifts obtained from chiral perturbation theory and using the virial expansion. In particular we study the equation of state and the behavior of the quark condensate as a function of the temperature and the density. [S0556-2821(99)07801-7]engjournal articlehttp://prd.aps.org/abstract/PRD/v59/i3/e034004http://prd.aps.orgopen access53Finite-TemperaturePerturbation-TheoryPhase-TransitionQcdCorrelatorsMesonsFísica (Física)22 Física