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The Spectator Electromagnetic Effect on Charged Pion Spectra in Peripheral Ultrarelativistic Heavy-Ion Collisions

Andrzej Rybicki·Antoni Szczurek
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Abstract

We estimate the electromagnetic effect of the spectator charge on the momentum spectra of $π^+$ and $π^-$ produced in peripheral Pb+Pb collisions at SPS energies. We find that the effect is large and results in strongly varying structures in the $x_F$ dependence of the $π^+/π^-$ ratio, especially at low transverse momenta where a deep valley in the above ratio is predicted at $x_F \sim$ 0.15 -- 0.20. It appears that the effect depends on initial conditions. Thus, it provides new information on the space and time evolution of the non-perturbative pion creation process.

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Andrzej Rybicki, Antoni Szczurek. 2006-10-10. The Spectator Electromagnetic Effect on Charged Pion Spectra in Peripheral Ultrarelativistic Heavy-Ion Collisions. https://doi.org/10.1103/physrevc.75.054903

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