Bunch-Crossing Identification for saturated calorimeter signals

This paper describes an algorithm, which will be implemented in the Preprocessor ASIC of the ATLAS Level-1 Calorimeter trigger. Its purpose is to identify the corresponding Bunch-Crossing in time for saturated trigger tower signals from the calorimeters (saturated BCID). Results presented here are combined from simulations with a PSPICE model of the Liquid Argon trigger tower electronics and the digital signal processing inside the Preprocessor. The PSPICE model describes saturation of analogue pulses in a realistic way. The digital processing allows to investigate noise effects and shifts of the digitization strobe of the FADC against the pulse position.