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Search for eta-mesic nuclei in photoproduction processes

G. A. Sokol·T. A. Aibergenov·A. V. Kravtsov·A. I. L'vov·L. N. Pavlyuchenko
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Abstract

We present preliminary results of an experiment performed at the 1-GeV electron synchrotron of the Lebedev Physical Institute. Using the bremsstrahlung photon beam with the end-point energy of 650-850 MeV and the carbon target, correlated pi+/n pairs with opening angle 180 deg and energies E_pi=300 MeV, E_n=100 MeV have been observed. They arise from the process gamma + 12C -> N + eta + (A-1) -> N + pi+ + n + (A-2) and provide evidence for the existence of eta-11B and eta-11C eta-mesic nuclei.

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G. A. Sokol, T. A. Aibergenov, A. V. Kravtsov, A. I. L'vov, L. N. Pavlyuchenko. 1999-10-11. Search for eta-mesic nuclei in photoproduction processes. https://arxiv.org/abs/nucl-ex/9905006

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