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arXiv · 0903.0235

Strong suppression of Coulomb corrections to the cross section of e+e- pair production in ultrarelativistic nuclear collisions

R. N. Lee·A. I. Milstein
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Abstract

The Coulomb corrections to the cross section of $e^+e^-$ pair production in ultrarelativistic nuclear collisions are calculated in the next-to-leading approximation with respect to the parameter $L=\ln \gamma_A\gamma_B$ ($\gamma_{A,B}$ are the Lorentz factors of colliding nuclei). We found considerable reduction of the Coulomb corrections even for large $\gamma_A\gamma_B$ due to the suppression of the production of $e^+e^-$ pair with the total energy of the order of a few electron masses in the rest frame of one of the nuclei. Our result explains why the deviation from the Born result were not observed in the experiment at SPS.

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R. N. Lee, A. I. Milstein. 2009-03-02. Strong suppression of Coulomb corrections to the cross section of e+e- pair production in ultrarelativistic nuclear collisions. https://doi.org/10.1134/s1063776109120073

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