RT Journal Article T1 Pion gas viscosity at low temperature and density A1 Dobado González, Antonio A1 Santalla Arribas, Silvia Noemí AB By using chiral perturbation theory and the Uehling-Uhlenbeck equation we compute the viscosity of a pion gas, in the low temperature and low density regime, in terms of the temperature and the pion fugacity. The viscosity turns out to be proportional to the square root of the temperature over the pion mass. Next to leading corrections are proportional to the temperature over the pion mass to 3/2. PB American Physical Society SN 0556-2821 YR 2002 FD 2002-05-01 LK https://hdl.handle.net/20.500.14352/58654 UL https://hdl.handle.net/20.500.14352/58654 LA eng NO ©The American Physical Society.The authors want to thank A. Gomez Nicola and J. R. Pelaez for reading the manuscript. This work has been partially supported by the Ministerio de Educación y Ciencia (Spain) (CICYT AEN 97-1693 and PB98-0782). NO CICYT NO Ministerio de Educación y Ciencia (Spain) DS Docta Complutense RD 4 abr 2025