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arXiv · 0704.3101

A new candidate for non-strangeness pentaquarks: N*(1675)

Seung-il Nam·Ki-Seok Choi·Atsushi Hosaka·Hyun-Chul Kim
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Abstract

We study a new nucleon resonance from eta photoproduction, which was observed at sqrt{s}=1675 MeV with a narrow decay width (~10 MeV) by the Tohoku LNS group as well as the GRAAL collaboration. Using an effective Lagrangian approach, we compute differential cross sections for the eta photoproduction. In addition to N*(1675,1/2+-,3/2+-), we employ six other nucleon resonances, i.e. N*(1520,1535,1650,1675,1710,1720) and vector meson exchanges which are the most relevant ones to this reaction process. As a result, we can reproduce the GRAAL data qualitatively well and observe obvious isospin asymmetry between the transition magnetic moments of N*(1675): mu_{gamma nn*} >> mu_{gamma pp*}, which indicates that the newly found nucleon resonance may be identified as a non-strange pentaquark state.

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Seung-il Nam, Ki-Seok Choi, Atsushi Hosaka, Hyun-Chul Kim. 2007-04-24. A new candidate for non-strangeness pentaquarks: N*(1675). https://doi.org/10.1143/ptps.168.97

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