Parity odd bubbles in hot QCD
Abstract
We consider the topological susceptibility for an SU(N) gauge theory in the limit of a large number of colors, . At nonzero temperature, the behavior of the topological susceptibility depends upon the order of the deconfining phase transition. The most interesting possibility is if the deconfining transition, at , is of second order. Then we argue that Witten's relation implies that the topological susceptibility vanishes in a calculable fashion at . As noted by Witten, this implies that for sufficiently light quark masses, metastable states which act like regions of nonzero --- parity odd bubbles --- can arise at temperatures just below . Experimentally, parity odd bubbles have dramatic signatures: the meson, and especially the meson, become light, and are copiously produced. Further, in parity odd bubbles, processes which are normally forbidden, such as , are allowed. The most direct way to detect parity violation is by measuring a parity odd global asymmetry for charged pions, which we define.
Cite
@article{arxiv.hep-ph/9808366,
title = {Parity odd bubbles in hot QCD},
author = {D. Kharzeev and R. D. Pisarski and M. H. G. Tytgat},
journal= {arXiv preprint arXiv:hep-ph/9808366},
year = {2007}
}
Comments
9 pages, LaTeX, requires sprocl.sty, to appear in the Proceedings of the 3rd workshop on "Continuous Advances in QCD", Minneapolis, 16-19 April, 1998