Determination of the Photon Detection Efficiency, Time and Spatial Resolution of the Light Collecting System of the near Liquid Argon Detector (ND-LAr) of the DUNE Experiment

DUNE is a long-baseline experiment for neutrino oscillation studies. Its near detector complex consists of three main parts. One of them is ND-LAr, the liquid argon time projection chamber (LAr-TPC). In LAr-TPC’s, a light collecting system (LCS) is commonly used as a trigger system. In this work the ND-LAr LCS is considered. The data from ProtoDUNE Dual Phase and Module 0 LAr-TPC prototypes was used to obtain the parameters of scintillation in liquid argon for Geant4 simulation. Then, the response of the Module 0 LCS in events with cosmic muons was compared with the response of its Geant4 model in identical simulated events to estimate the photon detection efficiency of the ND-LAr LCS. After that, single-particle and two-particle events with different shifts in time and space between tracks were simulated to determine the time and spatial resolution of the ND-LAr LCS. Obtained results allow us to judge whether the characteristics of the ND-LAr LCS satisfy the experiment requirements.