ISSN - 03702693, Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 2000, vol. 494, p. 26-32
Observation of the φ → η'γ decay with four charged particles and photons in the final state
Using 11.6 pb-1 of data collected in the energy range 0.864-1.06 Ge V by CMD-2 at VEPP-2M, the rare decay mode φ → η'γ was observed via the decay chain η' → π+π-η,η → π+π-π0 or η → π+π-γ. The following branching ratio was obtained: Br(φ → η'γ) = (4.9 -1.8/+2.2 ± 0.6) x 10-5. (C) 2000 Elsevier Science B.V.