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Search for the pentaquark via the P^0_{{c bar}s} --> phi,pi,p decay

E791 Collaboration·E. M. Aitala et al
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Abstract

We report results of the first search for the pentaquark P_{{c bar}s} which is predicted to be a doublet of states: P^0_{{c bar}s}=({c bar} s u u d) and P^-_{{c bar}s}=({c bar} s d d u). A search was made for the decay P^0_{{c bar}s} --> phi,pi,p in data from Fermilab experiment E791, in which 500 GeV/c pi^- beam interacted with nuclear targets. We present upper limits at 90% confidence level for the ratio of cross section times branching fraction of this decay to that for the decay D_s --> phi,pi. The upper limits are 0.031 and 0.063 for M(P^0_{{c bar}s}) = 2.75 and 2.86 GeV/c^2, respectively, assuming a P^0_{{c bar}s} lifetime of 0.4 ps.

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E791 Collaboration, E. M. Aitala et al. 1997-09-14. Search for the pentaquark via the P^0_{{c bar}s} --> phi,pi,p decay. https://doi.org/10.1103/physrevlett.81.44

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