In-medium production of 2π0, η, and π0 by π- at 750 MeV/c -: art. no. 055205

We present new data on 2pi(0) production by 750 MeV/c pi(-) on hydrogen and the complex nuclei C, Al, and Cu, in search of the proposed medium modifications of the f(0)(400-1200), or sigma, state. We have found that the pi(0)pi(0) invariant mass spectra for the four targets are different. The data indicate that nuclear absorption is mainly responsible for the change in the shape of the 2pi(0) invariant mass spectra for the complex targets. There is no hint of a narrow peak in the pipi invariant mass around 2m(pi). We have also measured single pi(0) and eta production on the above nuclei, in support of our investigation of nuclear final-state interaction processes. We observed strong eta absorption in nuclei.