Measurement of [formula omitted] in the S11 resonance

Abstract

We have measured the reaction p d→ 3 He η at a proton beam energy of 980 MeV, which is 88.5 MeV above threshold using the new `germanium wall' detector system. A missing-mass resolution of the detector system of 2.6% was achieved. The angular distribution of the meson is forward peaked. We found a total cross section of (573 ± 83 (stat.) ± 69 (syst.)) nb. The excitation function for the present reaction is described by a Breit Wigner form with parameters from photoproduction.