RT Journal Article
T1 Electrical conductivity of a pion gas
A1 Fernández Fraile, Daniel
A1 Gómez Nicola, Ángel
AB The electrical conductivity of a pion gas at low temperatures is studied in the framework of linear response and chiral perturbation theory. The standard ChPT power counting has to be modified to include pion propagator lines with a nonzero thermal width in order to properly account for collision effects typical of kinetic theory. With this modification, we discuss the relevant chiral power counting to be used in the calculation of transport coefficients. The leading order contribution is found and we show that the dominant higher order ladder diagrams can be treated as perturbative corrections at low temperatures. We find that the DC conductivity sigma(T) is a decreasing function of T, behaving for very low T as sigma(T)similar to e(2)m(pi) root m pi/T, consistently with nonrelativistic kinetic theory. When unitarization effects are included, sigma(T) increases slowly as T approaches the chiral phase transition. We compare with related works and discuss some physical consequences, especially in the context of the low-energy hadronic photon spectrum in relativistic heavy ion collisions.
PB Amer Physical Soc
SN 1550-7998
YR 2006
FD 2006-02
LK https://hdl.handle.net/20.500.14352/51391
UL https://hdl.handle.net/20.500.14352/51391
LA eng
NO © 2006 The American Physical Society.We are grateful to R. F. lvarez-Estrada, A. Dobado, F. J. LLanes-Estrada, and J. M. Martínez Resco for their useful comments. We also acknowledge financial support from the Spanish research projects No. FPA2004-02602, No. BFM2002-01003, No.  R27/05-13955-BSCH, No. FPA2005-02327, and from the Spanish F.P.I. programme (BES-2005-6726).
NO Spanish research projects
NO Spanish F.P.I. programme
DS Docta Complutense
RD 6 abr 2025