Search for eta-mesic nuclei in photo-mesonic processes
  Preliminary results of an experiment performed at the Lebedev Physical Institute with the bremsstrahlung photon beams of the end-point energies 650 and 850 MeV are presented. Correlated pi+n pairs with the opening angle theta = 180 deg and the energies E_\pi = 300 MeV, E_n = 100 MeV from the process gamma + 12C -> N + eta(A-1) -> N + pi+ n + (A-2) were observed. They provide an evidence for an existence of the eta-11B and eta-11C eta-mesic nuclei. 
G.A. Sokol, T.A. Aibergenov, A.V. Kravtsov, Yu.I. Krutov, A.I. L'vov,   L.N. Pavlyuchenko, S.S. Sidorin