Abnormal dilepton yield from parity breaking in dense nuclear matter

Abstract

At finite density parity can be spontaneously broken in strong interactions with far reaching implications. In particular, a time-dependent pseudoscalar background would modify QED by adding a Chern-Simons term to the lagrangian. As a striking consequence we propose a novel explanation for the dilepton excess observed in heavy ion collisions at low invariant masses. The presence of local parity breaking due to a time-dependent pseudoscalar condensate substantially modifies the dispersion relation of photons and vector mesons propagating in such a medium, changing the $\rho$ spectral function and resulting in a potentially large excess of dileptons with respect to the predictions based in a `cocktail' of known processes.

3 pages, 2 figures. Contributed to the International Conference on Quark Confinement and the Hadron Spectrum IX, Madrid, August 2010, to appear in the proceedings

References in corpus (1)

• Abnormal dilepton yield from local parity breaking in heavy-ion collisions

Cited by in corpus (5)

• An effective QCD Lagrangian in the presence of an axial chemical potential
• Dilepton excess from local parity breaking in baryon matter
• Evolution and fluctuations of chiral chemical potential in heavy ion collisions
• Chiral perturbation theory vs. Linear Sigma Model in a chiral imbalance medium
• Searching for P- and CP-odd effects in heavy ion collisions