Scintillating detector with SiPM readout for spatial resolution of cosmic muons

A scintillation detector with two-dimensional position resolution of a few mm and SiPM (Silicon-Photomultiplier) readout has been investigated with 160 GeV pions and cosmic muons. Position resolution in one direction is achieved by separation of the rectangular cross section into two trapezoidal sections of the plastic scintillator. Each trapezoid is optically insulated against the other. The amount of light produced by incoming particles is proportional to their path length and thus position dependent. The position resolution in the perpendicular direction is determined by the propagation time of the light. In both trapezoids the produced light is collected by 5 wavelength shifting fibers and guided to SiPMs. The SiPMs of each half are situated on opposite sites of the assembly. In this talk we report on the light output using WLS-Fibers and SiPM's and the achieved spatial resolution by the trapezoidal geometry.