Precision timing calorimeter for high energy physics

Abstract

Scintillator based calorimeter technology is studied with the aim to achieve particle detection with a time resolution on the order of a few 10 ps for photons and electrons at energies of a few GeV and above. We present results from a prototype of a 1.4x1.4x11.4 cm 3 sampling calorimeter cell consisting of tungsten absorber plates and Cerium-doped Lutetium Yttrium Orthosilicate (LYSO) crystal scintillator plates. The LYSO plates are read out with wave lengths shifting fibers which are optically coupled to fast photo detectors on both ends of the fibers. The measurements with electrons were performed at the Fermilab Test Beam Facility (FTBF) and the CERN SPS H2 test beam. In addition to the baseline setup plastic scintillation counter and a MCP-PMT were used as trigger and as a reference for a time of flight measurement (TOF). We also present measurements with a fast laser to further characterize the response of the prototype and the photo sensors. All data were recorded using a DRS4 fast samplig digitizer. These measurements are part of an R&D program whose aim is to demonstrate the feasibility of building a large scale electromagnetic calorimeter with a time resolution on the order of 10 picoseconds, to be used in high energy physics experiments.

On the Usage of Precision Timing Detectors in High Rate and High Pileup Environments

“…3, LYSO is well suited for precision timing measurements due to its very high light yield and very fast signal rise time [8,21]. The energy deposited in 1 mm of LYSO by a charged particle is about 1 MeV which results in the creation of about 30000 scintillation photons.…”