SIMULATION STUDIES OF THE MOLIERE RADIUS FOR EM CALORIMETER MATERIALS

The Monte-Carlo calculations of the Moliere radius (RM) for some homogeneous and heterogeneous media used in electromagnetic calorimetry in the energy range from 50 MeV to 10 GeV are presented in detail. The obtained results, the uncertainties in determining RM, estimations of the absorbed energy, methods for approximating the absorbed energy, and the accuracy of the results are discussed as well. Some RM are shown for calorimeter proto-types of the Spin Physics Detector experiment (SPD). A one-parameter function of the Moliere radius dependence on the absorber-scintillator thickness ratio is obtained.

CALCULATION OF THE MOLIÈRE RADIUS FOR VARIOUS CONFIGURATIONS OF AN ELECTROMAGNETIC SAMPLING CALORIMETER ECaL SPD NICA

One of the main tasks of the electromagnetic calorimetry of the SPD setup is effective π0-γ separation in the energy range from 50 MeV to 10 GeV. Therefore, the current task is to optimize the design of the module cells in order to improve the physical parameters of the ECaL calorimeter. The Molière radius is determined in this work by the Monte Carlo method using Geant4 toolkit for various cell configurations of the calorimeter module. The results obtained in this work will be taken into account in the further development of the detecting systems of the ECaL SPD NICA.

Commissioning the ATLAS Liquid Argon Calorimeter Phase-I Upgrade

Liquid argon (LAr) sampling calorimeters are employed by ATLAS for all electromagnetic calorimetry in the pseudo-rapidity region η < 3.2, and for hadronic and forward calorimetry in the region from η = 1.5 to η = 4.9. In the first LHC run (Run-1), a total luminosity of around 26 fb-1 was collected at centre-of-mass energies of 7-8 TeV. After detector consolidation during a long shut-down, Run-2 started in 2015 and around 150 fb-1 of data at a centre-of-mass energy of 13 TeV was recorded. With the end of Run-2 in 2018, a multi-year shutdown for the Phase-I detector upgrades began. As part of the Phase-I upgrade, new trigger readout electronics of the ATLAS LAr Calorimeter have been developed. Installation be-gan at the start of the LHC shut down in 2019 and is expected to be completed in 2020. A commissioning cam-paign is underway in order to realise the capabilities of the new, higher granularity and higher precision level-1 trigger hardware in Run-3 data taking. This contribution will give an overview of the new trigger readout system and the ongoing commissioning and installation efforts.