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arXiv · 1012.0744

Abnormal dilepton yield from parity breaking in dense nuclear matter

Alexander Andrianov·Vladimir Andrianov·Domenec Espriu·Xumeu Planells
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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 $ρ$ spectral function and resulting in a potentially large excess of dileptons with respect to the predictions based in a `cocktail' of known processes.

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Alexander Andrianov, Vladimir Andrianov, Domenec Espriu, Xumeu Planells. 2010-12-03. Abnormal dilepton yield from parity breaking in dense nuclear matter. https://doi.org/10.1063/1.3575058

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