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Impact-Parameter Dependence of Multiple Lepton-pair Production from Electromagnetic Fields

M. C. Guclu·J. C. Wells·A. S. Umar·M. R. Strayer·D. J. Ernst
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Abstract

In relativistic heavy-ion collisions, the strong Lorentz-contracted electromagnetic fields are capable of producing copious numbers of lepton pairs through the two-photon mechanism. Monte Carlo techniques have been developed that allow the exact calculation of production by this mechanism when a semi-classical approximation is made to the motion of the two ions. Here, we develop a hybrid Monte Carlo technique that enables us to calculate the impact parameter dependence of the two-photon mechanism for lepton-pair production, and by using this result, we obtain the probability distribution for multiple-pair production as a function of impact parameter. Computations are performed for S$+$Au and Pb$+$Pb systems at 200 A GeV and 160 A GeV, respectively. We also compare our results with the equivalent photon approximation and elucidate the differences.

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M. C. Guclu, J. C. Wells, A. S. Umar, M. R. Strayer, D. J. Ernst. 1994-10-26. Impact-Parameter Dependence of Multiple Lepton-pair Production from Electromagnetic Fields. https://doi.org/10.1103/physreva.51.1836

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