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arXiv · 1003.4585

Evidence for Narrow N*(1685) Resonance in Quasifree Compton Scattering on the Neutron

V. Kuznetsov·M. V. Polyakov·V. Bellini·T. Boiko·S. Chebotarev·H. S. Dho·G. Gervino·F. Ghio·A. Giusa·A. Kim·W. Kim·F. Mammoliti·E. Milman·A. Ni·I. A. Perevalova·C. Randieri·G. Russo·M. L. Sperduto·C. M. Sutera·A. N. Vall
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Abstract

The first study of quasi-free Compton scattering on the neutron in the energy range of $E_{\gamma}=0.75 - 1.5$ GeV is presented. The data reveals a narrow peak at $W\sim 1.685$ GeV. This result, being considered in conjunction with the recent evidence for a narrow structure at $W\sim 1.68$GeV in the $\eta$ photoproduction on the neutron, suggests the existence of a new nucleon resonance with unusual properties: the mass $M\sim 1.685$GeV, the narrow width $\Gamma \leq 30$MeV, and the much stronger photoexcitation on the neutron than on the proton.

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V. Kuznetsov, M. V. Polyakov, V. Bellini, T. Boiko, S. Chebotarev, H. S. Dho, G. Gervino, F. Ghio, A. Giusa, A. Kim, W. Kim, F. Mammoliti, E. Milman, A. Ni, I. A. Perevalova, C. Randieri, G. Russo, M. L. Sperduto, C. M. Sutera, A. N. Vall. 2010-03-24. Evidence for Narrow N*(1685) Resonance in Quasifree Compton Scattering on the Neutron. https://doi.org/10.1103/physrevc.83.022201

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