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arXiv · 0710.5118

Anti-nuclei and nuclei production in Pb+Pb collisions at CERN SPS energies

Abstract

We present new results on production of 3He and t obtained by the NA49 experiment in 20A, 30A, 40A and 80A GeV central Pb+Pb collisions at the CERN SPS. Transverse mass spectra and rapidity distributions for clusters measured over a large phase space domain are discussed. We observe a weak dependence of the mid-rapidity t/3He ratio on collision energy at SPS. The energy dependence of the total yield for 3He is remarkably reproduced by a statistical hadron gas model. A gradual decrease of the coalescence parameter B3 for 3He with $\sqrt {s_{NN}}$ is observed.In addition, a measurement of the yield of anti-deuterons in Pb+Pb reactions at SPS's top energy of $\sqrt {s_{NN}}$ = 17.2 GeV is presented.

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BibTeXRIS

V. I. Kolesnikov. 2007-10-26. Anti-nuclei and nuclei production in Pb+Pb collisions at CERN SPS energies. https://doi.org/10.1088/1742-6596%2F110%2F3%2F032010

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