Event-by-event fluctuations of magnetic and electric fields in heavy ion collisions

Abstract

We show that fluctuating proton positions in the colliding nuclei generate, on the event-by-event basis, very strong magnetic and electric fields in the direction both parallel and perpendicular to the reaction plane. The magnitude of E and B fields in each event is of the order of m_pi^2 \approx 10^18 Gauss. Implications on the observation of electric dipole in heavy ion collisions is discussed, and the possibility of measuring the electric conductivity of the hot medium is pointed out.

Comments: 10 pages, 5 figures, new comments in section 3, to appear in Phys. Lett. B