Abstract
We discuss and propose the minimal generalization of the Witten-Veneziano relation to finite temperatures, prompted by STAR and PHENIX experimental results on the multiplicity of mesons. After explaining why these results show that the zero-temperature Witten-Veneziano relation cannot be straightforwardly extended to temperatures too close to the chiral restoration temperature and beyond, we find the quantity which should replace, at , the Yang-Mills topological susceptibility appearing in the Witten-Veneziano relation, in order to avoid the conflict with experiment at . This is illustrated through concrete -dependences of pseudoscalar meson masses in a chirally well-behaved, Dyson-Schwinger approach, but our results and conclusions are of a more general nature and, essentially, model-independent.
- Received 3 May 2011
DOI:https://doi.org/10.1103/PhysRevD.84.016006
© 2011 American Physical Society