Search for exotic baryons in double radiative capture on pionic hydrogen
  We report a search for low-lying exotic baryons via double radiative capture on pionic hydrogen. The data were collected at the TRIUMF cyclotron using the RMC spectrometer by detecting gamma-ray pairs from pion stops in liquid hydrogen. No evidence was found to support an earlier claim for exotic baryons of masses 1004 and 1044 MeV/$c^2$. We obtain upper limits on the branching ratios for double radiative capture via these exotic states of $< 3 \times 10^{-6}$ and $< 4 \times 10^{-6}$ respectively. 
P.A.Zolnierczuk, D.S.Armstrong, E.Christy, J.H.D.Clark, T.P.Gorringe,   M.D.Hasinoff, M.A.Kovash, S.Tripathi, and D.H.Wright