Performance of a spaghetti calorimeter prototype with tungsten absorber and garnet crystal fibres
L. An, E. Auffray, F. Betti, F. Dall’Omo, D. Gascón, A. Golutvin, Yu. Guz, S. Kholodenko, L. Martinazzoli, J. Mazorra de Cos, E. Picatoste Olloqui, M. Pizzichemi, P. Roloff, Matteo Salomoni, David Sánchez, A. Schopper, A. Semennikov, P. B. Shatalov, E. Shmanin, D. Strekalina, Yamin Zhang
Abstract
A spaghetti calorimeter (SPACAL) prototype with scintillating crystal fibres was assembled and tested with electron beams of energy from 1 to 5 GeV. The prototype comprised radiation-hard Cerium-doped Gd3Al2Ga3O12 (GAGG:Ce) and Y3Al5O12 (YAG:Ce) embedded in a pure tungsten absorber. The energy resolution was studied as a function of the incidence angle of the beam and found to be of the order of 10%/E⊕1%, in line with the LHCb Shashlik technology. The time resolution was measured with metal channel dynode photomultipliers placed in contact with the fibres or coupled via a light guide, additionally testing an optical tape to glue the components. Time resolution of a few tens of picosecond was achieved for all the energies reaching down to (18.5 ± 0.2) ps at 5 GeV.