Investigation of the decay {eta}' {yields} 3{pi}{sup 0} with the GAMS-4{pi} spectrometer

An experiment performed with the GAMS-4{pi} spectrometer resulted in observing 235 {+-} 45 events of the decay {eta}' {yields} 3{pi}{sup 0}. The respective charge-exchange reaction at a momentum of 32.5 GeV/c was used as a source of {eta}' mesons. The decay branching ratio was found to be Br({eta}' {yields} 3{pi}{sup 0}) = (1.8 {+-} 0.4) x 10{sup -3}. The slope parameter of the square of the respective matrix element in the linear approximation proved to be {beta} = -0.59 {+-} 0.18.