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arXiv · 1010.4688

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

Alexander Andrianov·Vladimir Andrianov·Domenec Espriu·Xumeu Planells
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Abstract

We propose a novel explanation for the dilepton excess observed in heavy ion collisions at invariant masses below 1 GeV. We argue that the presence of local parity breaking due to a time-dependent isosinglet and/or isotriplet 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 e+e- and \mu+\mu- with respect to the theoretical predictions based in a 'cocktail' of known hadronic processes. Possible signatures to prove or disprove this effect are discussed.

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Alexander Andrianov, Vladimir Andrianov, Domenec Espriu, Xumeu Planells. 2010-10-22. Abnormal dilepton yield from local parity breaking in heavy-ion collisions. https://arxiv.org/abs/1010.4688

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