Search for exotic baryons in double radiative capture on pionic hydrogen

Abstract

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.

13 pages, 4 figures

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Cited by in corpus (2)

• Pentaquark Theta^+(1540) production in gamma N --> K Anti-K N
• Double radiative pion capture on hydrogen and deuterium and the nucleon's pion cloud