Luminosity determination at ANKE with different reference reactions

A high precision measurement on the mass of the eta meson was the main objective of the COSY proposal Nr. 187. In detail the meson production reaction dp → 3HeX has been studied with X being the eta meson identified by the missing mass technique. However, parallel to the already very successfully performed eta mass determination, the obtained data also allow for studies on total and differential cross sections for the reaction dp → 3Heη close to threshold as well as for a study of the ABC-effect in the channel dp → 3Heπ+π-. For this purpose a careful data normalization and luminosity determination is required. While dp-elastic scattering is commonly used as reference reaction for the luminosity determination at ANKE, an independent normalization channel is of high interest as cross reference. Therefore, the 3Heπ0 final state is analyzed in parallel and the results are compared to the dp-elastic scattering data. The method and recent results are presented.