Test beam results with LuAG fibers for next-generation calorimeters

For the next generation of calorimeters, designed to improve the energy resolution of hadrons and jet measurements, there is a need for highly granular detectors that require peculiar geometries. Inorganic scintillators can provide good stopping power to allow compact calorimeter designs together with an excellent energy resolution.The micropulling-down technique allows to grow crystal fibers with high aspect ratio providing good granularity. Designs based on dual-readout could also be considered since the host matrices of extrinsic scintillators behave as a Cherenkov radiator in the absence of the scintillating dopant.We report here about results obtained with crystal fibers of 22 cm length and 2 mm diameter of lutetium aluminium garnet (LuAG, Lu3Al5O12).The response of such fibers in a high energy physics environment has been investigated through a test beam campaign at the CERN PS facility using electrons in the 50–150 GeV energy range.The results, proving the potential of LuAG fibers for calorimetry applications, have been used to validate a Geant4 simulation which allowed to study different configuration of a fiber-based detector. Possible implementations of the crystal fibers technology into a real calorimeter are also discussed.