Eur. Phys. J. C (2009) 62: 69-73
https://doi.org/10.1140/epjc/s10052-009-0996-0

Regular Article - Theoretical Physics

Sigma mesonic mode near the QCD critical point

Institute of Physics, University of Tokyo, Komaba, Tokyo, 153-8902, Japan

^* e-mail: hfujii@phys.c.u-tokyo.ac.jp

Received: 9 October 2008
Revised: 4 February 2009
Published online: 8 April 2009

Abstract

Properties of the QCD critical point, an endpoint of the first order boundary line in the temperature T–baryochemical potential μ _B plane, are discussed with the Nambu–Jona-Lasinio model. It is demonstrated that the softening of the sigma mesonic mode is inherent to the crossover transition of the chiral symmetry while the spectral enhancement of the particle–hole mode near zero frequency is associated with the QCD critical point. Phenomenological implications in heavy-ion experiments are mentioned briefly.