SiΛΛViO: A trigger for ΛΛ-Hyperons

The production of bound kaon–nucleon-states (kaonic-cluster) in the reaction p+p→[ppK-]+K+p+p→[ppK-]+K+ should be investigated in a dedicated measurement at the FOPI detector system at the SIS-accelerator of GSI, by looking for the decay [ppK-]→p+Λ→p+p+π-[ppK-]→p+Λ→p+p+π-. To select the final states, the detector system SiΛViOSiΛViO has been build up as a trigger for ΛΛ-Hyperons. This detector consists of two layers of segmented silicon-strip-detectors, which are able to measure online the particle multiplicity. These two layers are arranged such, that most of the ΛΛ-Hyperons will decay between them. The trigger signal is generated by comparing online the hit multiplicity on the two layers.