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Lambda production in central Pb+Pb collisions at CERN-SPS energies

A. Mischke
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Abstract

In this paper we present recent results from the NA49 experiment for $Λ$ and $\barΛ$ hyperons produced in central Pb+Pb collisions at 40, 80 and 158 A$\cdot$GeV. Transverse mass spectra and rapidity distributions for $Λ$ are shown for all three energies. The shape of the rapidity distribution becomes flatter with increasing beam energy. The multiplicities at mid-rapidity as well as the total yields are studied as a function of collision energy including AGS measurements. The ratio $Λ/π$ at mid-rapidity and in 4$π$ has a maximum around 40 A$\cdot$GeV. In addition, $\barΛ$ rapidity distributions have been measured at 40 and 80 A$\cdot$GeV, which allows to study the $\barΛ$/$Λ$ ratio.

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A. Mischke. 2002-01-22. Lambda production in central Pb+Pb collisions at CERN-SPS energies. https://doi.org/10.1088/0954-3899%2F28%2F7%2F330

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