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Pentaquark baryon production at the Relativistic Heavy Ion Collider

Lie-Wen Chen·V. Greco·C. M. Ko·S. H. Lee·W. Liu
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Abstract

Production of pentaquark $Θ^+$ baryons in central relativistic heavy ion collisions is studied in a kinetic model. Assuming that a quark-gluon plasma is produced in the collisions, we first determine the number of $Θ^+$ produced from the quark-gluon plasma using a parton coalescence model, and then take into consideration its production and absorption in subsequent hadronic matter via the reactions $KN\leftrightarrowΘ$, $KN\leftrightarrowπΘ$, and $\piN\leftrightarrow\bar KΘ$. We find that although the final $Θ^+$ number is affected by hadronic interactions, it remains sensitive to the initial number of $Θ^+$ produced from the quark-gluon plasma, particularly in the case of a small $Θ^+$ width as imposed by the $K^+N$ and $K^+d$ scattering data. Because of small baryon chemical potential in the hot dense matter produced in these collisions, the number of produced anti-$Θ$ is only slightly smaller than that of $Θ^+$.

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Lie-Wen Chen, V. Greco, C. M. Ko, S. H. Lee, W. Liu. 2004-09-23. Pentaquark baryon production at the Relativistic Heavy Ion Collider. https://doi.org/10.1016/j.physletb.2004.09.027

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