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Exotic particle searches with STAR at RHIC

Sonia Kabana
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Abstract

We present preliminary results of the STAR experiment at RHIC on exotic particle searches in minimum bias Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. We observe a narrow peak at 1734 $\pm$ 0.5 $\pm$ 5 MeV in the $ΛK^0_s$ invariant mass with width consistent with the experimental resolution of about 6 MeV within the errors. The statistical significance can be quantified between 3 and 6 $σ$ depending on cuts and methods. If this peak corresponds to a real particle state it would be a candidate for the $N^0$ or the $Ξ^0$ I=1/2 pentaquark states.

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Sonia Kabana. 2004-06-11. Exotic particle searches with STAR at RHIC. https://doi.org/10.1556/aph.24.2005.1-4.44

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