Evidence for narrow resonant structures at $W\approx 1.68$ and $W\approx 1.72$ GeV in real Compton scattering off the proton

Abstract

First measurement of the beam asymmetry $\Sigma$ for Compton scattering off the proton in the energy range $E_{\gamma }=0.85-1.25$ GeV is presented. The data reveals two narrow structures at $E_{\gamma }=1.036$ and $E_{\gamma }=1.119$ GeV. They may signal narrow resonances with masses near $1.68$ and $1.72$ GeV, or they may be generated by the sub-threshold $K\Lambda$ and $\omega p$ production. Their decisive identification requires additional theoretical and experimental efforts.

arXiv commentPublished version

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Cited by in corpus (15)

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