The silicon detector of the PHOBOS experiment at RHIC

The PHOBOS experiment is designed to study relativistic heavy-ion collisions at RHIC, combining a multiplicity counter with a multiparticle spectrometer. The multiplicity section will measure the particle multiplicity over the full solid angle. The spectrometer will be able to reconstruct tracks and identify particles at mid-rapidity. The detector consists of silicon pad detectors which provides full two-dimensional position resolution and multiplicity information. A double metal layer technique is used for connecting the pads to the electronics. This simplifies the readout of grid-like pad configurations and minimizes multiple scattering. The overall layout of the experiment and the readout technique used for the silicon detector is presented together with test results of first prototypes.