A Search for Sigma^0_5, N^0_5 and Theta^++ Pentaquark States

Abstract

A high-resolution (sigma_instr. = 1.5 MeV) search for narrow states (Gamma < 10 MeV) with masses of M_x approx 1500-1850 MeV in ep -> e'K^+ X, e'K^- X and e' pi^+ X electroproduction at small angles and low Q^2 was performed. These states would be candidate partner states of the reported Theta^+(1540) pentaquark. No statistically significant signal was observed in any of the channels at 90% C.L. Upper limits on forward production were determined to be between 0.7% and 4.2% of the Lambda(1520) production cross section, depending on the channel and the assumed mass and width of the state.

5 pages, 5 figures, to appear in Phys. Rev. C, update with responses to referee suggestions

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Cited by in corpus (3)

• High Resolution Spectroscopy of 12B_Lambda by Electroproduction
• Present status on experimental search for pentaquarks
• Properties of the Lambda(1520) Resonance from High-Precision Electroproduction Data