Speaker
Description
Collaboration
R. Becker, G. Dissertori, L. Djambazov, M. Donegà, M. Dröge, C. Haller, U. Horisberger, W. Lustermann, F. Nessi-Tedaldi, M. Quittnat, F. Pandolfi, M.Peruzzi, M. Schoenenberger ETH Zürich
F. Cavallari, I. Dafinei, M. Diemoz, G. D'Imperio, D. del Re, S. Gelli, C. Jorda Lope, P. Meridiani, F. Micheli, M. Nuccetelli, G. Organtini, R. Paramatti, F. Pellegrino, S. Rahatlou, C. Rovelli, F. Santatanasio, L. Soffi Università Sapienza and INFN Roma
T. Tabarelli de Fatis, A. Martelli INFN Milano-Bicocca
N. Pastrone INFN Torino
V. Candelise, G. Della Ricca Università degli Studi di Trieste and INFN Trieste
Summary
Experiments are considering upgrades to their detectors for running at the future High-Luminosity LHC collider at CERN (HL-LHC) after 2022, because of the stringent requirements imposed by the high rates of ionising radiation. One of the options considered for an electromagnetic calorimeter is a design using cerium fluoride scintillating crystals as active material, interleaved with heavy absorber plates, and read out by wavelength-shifting (WLS) fibers. Experiments are considering upgrades to their detectors for running at the future High-Luminosity LHC collider at CERN (HL-LHC) after 2022, because of the stringent requirements imposed by the high rates of ionising radiation.
One of the options considered for an electromagnetic calorimeter is a design using cerium fluoride scintillating crystals as active material, interleaved with heavy absorber plates, and read out by WLS fibers.
The presentation will summarize the results of two different beam tests: data from electrons of energies up to 500 MeV were collected at the INFN Frascati laboratories' Beam Test Facility (BTF), whereas higher-energy electrons were produced in the SPS accelerator complex at CERN. The results will focus on energy resolution studies.
The scintillator and absorber dimensions have been optimised for this test, to give an adequate granularity and sampling fraction, while minimising the amount of scintillator needed. In this study a single channel is used, comprising 10 (15) samplings for a total of 17 (25) X_0, respectively for the BTF (SPS) data-taking. Its transverse cross section is 24x24 mm^2. The active samples are 10 mm thick, while each absorber layer thickness is 3.1 mm.
While R&D is being performed by several material science and high-energy physics groups worldwide to develop radiation resistant WLS fibers suitable for use at the HL-LHC, conventional 3HF, single-clad plastic fibers from Kuraray have been implemented as WLS for this test, since it has been demonstrated that they are photo-luminescent in the range of wavelengths of the cerium fluoride scintillation emission. The light from each WLS fiber is read out individually by a Hamamatsu R1450 photomultiplier.
The electron energy resolution of the single calorimeter tower was studied as a function of the beam energy and proven to be in very good agreement with Montecarlo expectations. The stochastic term of the energy resolution that can be obtained from this geometry is about 10%/sqrt(E).
This work was performed with the support of the Swiss National Science Foundation and the Istituto Nazionale di Fisica Nucleare.
