The HERMES silicon project

A silicon detector system will be added to the HERMES experiment at DESY. The acceptance of the front region will be enlarged with a view to increase the fraction of Λ0, Λc+, and J/Ψ-particles which can be reconstructed. The detector is located inside the ring vacuum. This report describes some details of the design, the cooling and the read-out of the detector. The first parts of the detector have recently been installed in the experiment. It is expected that the full detector will be installed in the fall of 1999.