Characterization of an irradiated double-sided silicon strip detector with fast binary readout electronics in a pion beam

We report on the characterization of an AC-coupled, double-sided silicon strip detector, with fast binary readout electronics, in a pion beam before and after proton irradiation. The proton irradiation was non-uniform and to increase the damage the detector was heated to accelerate the anti-annealing. The effective radiation level was about 1/spl times/10/sup 14/ p/cm/sup 2/. Both the bias voltage of the detector and the threshold of the discriminator of the binary readout electronics were varied, and the efficiencies were determined. The irradiated detector clearly shows the effect of bulk inversion. The binary system proved to be efficient well below the full depletion voltage on the p-n junction side. Due to the highly non-uniform irradiation, the depletion voltage changes from close to zero to about 120 V along a single strip, but the detector appears to work without any noticeable failures.