SiLViO: A Trigger for Lambda-Particles

Abstract

The production of bound kaon-nucleon-states (kaonic-cluster) in the reaction $p_s16pto [ppK^{-}] _s16 K^{_s16}$ should be investigated in a dedicated measurement at the FOPI detector system at the SIS-accelerator of GSI, by looking for the decay $ppK^{-} to p _s16 Lambda to p _s16 p _s16 pi^{-}$. To select the final states, the detector system Si$Lambda$ViO has been build up as a trigger for $Lambda$-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 $Lambda$-Hyperons will decay between them. The trigger signal is generated by comparing online the hit multiplicity on the two layers.