RT Journal Article
T1 Bulk viscosity and the conformal anomaly in the pion gas
A1 Fernández Fraile, Daniel
A1 Gómez Nicola, Ángel
AB We calculate the bulk viscosity of the massive pion gas within unitarized chiral perturbation theory. We obtain a low-temperature peak arising from explicit conformal breaking due to the pion mass and another peak near the critical temperature, dominated by the conformal anomaly through gluon condensate terms. The correlation between bulk viscosity and conformal breaking supports a recent QCD proposal. We discuss the role of resonances, heavier states, and large-N(c) counting.
PB American Physical Society
SN 0031-9007
YR 2009
FD 2009-03-27
LK https://hdl.handle.net/20.500.14352/44580
UL https://hdl.handle.net/20.500.14352/44580
LA eng
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NO © 2009 The American Physical Soci.We are grateful to D. Kharzeev, G. D. Moore, and C. Pica for very useful comments. This research was partially funded by research contracts No. FPA2004-02602, No. FPA2005-02327, No. FPA2007-29115-E, No. PR34- 1856-BSCH, No. UCM-CAM  10309, and No. FPI-BES- 2005-6726.
NO UCM-CAM
DS Docta Complutense
RD 28 abr 2024