Study of the calorimetric performance of a liquid Argon detector based on a novel optical imaging concept

DUNE is a next-generation long-baseline neutrino oscillation experiment. It aims to measure the still unknown $ \delta_{CP} $ violation phase and the sign of $ \Delta m_{13}^2 $, which defines the neutrino mass ordering. DUNE will exploit a Far Detector composed of four multi-kiloton LArTPCs, and a Near Detector (ND) complex located close to the neutrino source at Fermilab. The SAND detector at the ND complex is designed to perform on-axis beam monitoring, constrain uncertainties in the oscillation analysis and perform precision neutrino physics measurements. SAND includes a 0.6 T super-conductive magnet, an electromagnetic calorimeter, a 1-ton liquid Argon detector - GRAIN - and a modular, low-density straw tube target tracker system. GRAIN is an innovative LAr detector where neutrino interactions can be reconstructed using only the LAr scintillation light imaged by an optical system based on Coded Aperture masks and lenses - a novel approach never used before in particle physics applications. In this thesis, a first evaluation of GRAIN track reconstruction and calorimetric capabilities was obtained with an optical system based on Coded Aperture cameras. A simulation of $\nu_\mu + Ar$ interactions with the energy spectrum expected at the future Fermilab Long Baseline Neutrino Facility (LBNF) was performed. The performance of SAND was evaluated, combining the information provided by all its sub-detectors, on the selection of $ \nu_\mu + Ar \to \mu^- + p + X $ sample and on the neutrino energy reconstruction.

Calorimetric efficiency of the DUNE experiment

The Deep Underground Neutrino Experiment is a long-baseline neutrino experiment which is under construction in the United States. It will be composed of a Near Detector system located a few hundred meters from the neutrino source at Fermilab and a far detector system composed of four multi-kt LArTPCs at Sanford Underground Research Facility in South Dakota. The experiment will measure the leptonic CP violation phase of the PMNS matrix and discriminate the ordering of neutrino masses. Additional physics goals include detection of neutrinos from supernovae collapse and search for possible proton decay. One component of the Near detector complex is the System for on-Axis Neutrino Detection apparatus, which includes GRanular Argon for Interaction of Neutrinos, a novel liquid Argon detector that aims at imaging neutrino interactions using scintillation light collected by optical system and read-out by SIPM matrix. This thesis work aims at studying the GRAIN performances as a homogeneous calorimeter, able to measure the energy deposited by charged particles in LAr through scintillation photons emitted along their path inside the vessel. The energy calibration of the liquid argon volume required to write (and validate) an efficient software for the detector response simulation to the arrival of scintillation photons.