Construction, performance and modeling of a compact SciFi hodoscope for use in detector testing at various test beams

Abstract

It is quite common practice to test detectors for high energy physics experiments using test beams, produced at various accelerator facilities. A key component of every test setup is a trigger system, which usually has to be provided by the team preparing the test. Therefore, a compact scintillating fiber detector has been built, with the aim of working as a position sensitive trigger device for testing Shashlyk-type modules of a new electromagnetic calorimeter (ECAL0), being built for the COMPASS experiment. A description of the construction of the detector is presented, followed by its performance evaluation using a low-intensity electron beam from the ELSA accelerator and electrons at the T10 test beam in CERN. The detector was adapted for use with acquisition system based on an 80 MSPS, 12-bit analog-to-digital converters. An effort has been made to develop a full Monte-Carlo model of the system, which includes simulation of particle interactions, detector optics, photomultiplier, signal acquisition electronics (both ADC and shaping, incl. noise simulation) and finally signal quantization, ADC non-linearity and its clock jitter.