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Dilepton production by bremsstrahlung of meson fields in nuclear collisions

I. N. Mishustin·L. M. Satarov·H. Stoecker·W. Greiner
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Abstract

We study the bremsstrahlung of virtual omega mesons due to the collective deceleration of nuclei at the initial stage of an ultrarelativistic heavy-ion collision. It is shown that electromagnetic decays of these mesons may give an important contribution to the observed yields of dileptons. Mass spectra of positron-electron and muon pairs produced in central Au+Au collisions are calculated under some simplifying assumptions on the space-time variation of the baryonic current in a nuclear collision process. Comparison with the CERES data for 160 AGev Pb+Au collisions shows that the proposed mechanism gives a noticeable fraction of the observed lepton pairs in the intermediate region of invariant masses. Sensitivity of the dilepton yield to the in-medium modification of masses and widths of vector mesons is demonstrated.

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I. N. Mishustin, L. M. Satarov, H. Stoecker, W. Greiner. 1997-09-17. Dilepton production by bremsstrahlung of meson fields in nuclear collisions. https://doi.org/10.1103/physrevc.57.2552

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