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arXiv · hep-ph/0103073

Open charm enhancement by secondary interactions in relativistic nucleus-nucleus collisions?

W. Cassing·L. A. Kondratyuk·G. I. Lykasov·M. V. Rzjanin
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Abstract

We calculate open charm production in $Pb+Pb$ reactions at SPS energies within the HSD transport approach - which is based on string, quark, diquark ($q, \bar{q}, qq, \bar{q}\bar{q}$) and hadronic degrees of freedom - including the production of open charm pairs from secondary 'meson'-'baryon' (or quark-diquark and antiquark-diquark) collisions. It is argued that at collision energies close to the $c\bar{c}$ pair threshold the dominant production mechanism is related to the two body (or quasi two body) reactions $πN \to \bar{D} (\bar{D^*}) Λ_c, (Σ_c)$. Estimates within the framework of the Quark-Gluon String model suggest cross sections of a few $μb$ for $πN \to \bar{D} Λ_c$ in the region of 1 GeV above threshold. The dynamical transport calculations for $Pb + Pb$ at 160 A$\cdot$GeV indicate that the open charm enhancement reported by the NA50 Collaboration might be due to such secondary reaction mechanisms.

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W. Cassing, L. A. Kondratyuk, G. I. Lykasov, M. V. Rzjanin. 2001-03-07. Open charm enhancement by secondary interactions in relativistic nucleus-nucleus collisions?. https://doi.org/10.1016/s0370-2693(01)00744-4

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