Measurement of the eta(1440)->K*-K0(L)pi-+ production rates froma anti-p p annihilation at rest qt three different hydrogen target densities

Abstract

From the study of the annihilation at rest pbar p --> K*K0miss pi-+ pi+- pi-, the production rates of the eta( 1440) -->K+-K0long pi-+ were obtained for three different hydrogen target densities: liquid, gaseous at NTP and at low pressure (5 mbar). The rate values are: f(LH) = (6.0+-0.5) . 10e4, f(NTP) = (2.9 +-0.4) . 10e4 and f(5 mbar) = (1.0 +-0.2) . 10e4. From these results, the density dependence of the annihilation fraction from the 1S0 protonium level can be extracted directly