PERFORMANCE OF THE DELPHI SMALL-ANGLE TILE CALORIMETER

The DELPHI STIC detector is a lead-scintillator sampling calorimeter w ith wave length shifting optical fibers used for light collection. The main goal of the calorimeter at LEP100 is to measure the luminosity w ith an accuracy better than 0.1%. The detector has been in operation s ince the 1994 LEP run. Presented here is the performance measured duri ng the 1994-1995 LEP runs, with the emphasis on the achieved energy an d space resolution, the long-term stability and the efficiency of the detector. The new bunch-trains mode of LEP requires a rather sophistic ated trigger and timing scheme which is also presented. To control the trigger efficiency and stability of the calorimeter channels, a LED-b ased monitoring system has been developed.