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Search for the $\barΘ^- \to $ K$^-$ $\bar{n}$ with PHENIX

C. Pinkenburg
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Abstract

The PHENIX experiment at RHIC should be sensitive to decays of the the anti--pentaquark $\barΘ^-$ via the K$^-$ $\bar{n}$ channel. Charged kaons can be identified using the standard tracking and time of flight up to a momentum of 1.5 GeV/c. Anti--neutron candidates are detected via their annihilation signal in the highly segmented electromagnetic calorimeter (EMCal). In order to assess the quality of the anti--neutron identification we reconstruct the $\barΣ \to \bar{n}π$. As an additional crosscheck the invariant mass of K$^+$ $\bar{n}$ is reconstructed where no resonance in the pentaquark mass range is expected. At the present time no enhancement at the expected pentaquark mass is observed in dAu collisions at $\sqrt{s_{NN}} = 200 GeV.

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C. Pinkenburg. 2004-03-31. Search for the $\barΘ^- \to $ K$^-$ $\bar{n}$ with PHENIX. https://doi.org/10.1088/0954-3899%2F30%2F8%2F090

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