Neutron identification in DUNE and proto-DUNE
IDPASC Portugal - PHD Programme 2019
2019 / 2020
Experimental Particle Physics
Faculdade de Ciências - Universidade de Lisboa
Laboratório de Instrumentação e Física Experimental de Partículas
The DUNE experiment is designed to measure the last unknown parameters of neutrino oscillations, namely the mass ordering between the three neutrino states, and the CP-violation phase – which may be a fundamental ingredient to explain the matter / anti-matter asymmetry in the Universe. DUNE will be a long base line experiment, measuring the oscillations of neutrino and anti-neutrino beams, 1300 km away from their production point at Fermilab, USA. Four 10 kTon detectors are planned, the first one should be ready in 2025, one or two years before the beam starts. A much smaller prototype of the first DUNE detector is already the largest Liquid Argon detectors ever built: it is a Time Projection Chamber (TPC) with 6.9 x 7.2 x 6.0 m3. This detector is installed at CERN, and has collected data from interactions from beams of protons and pions of different energies, and samples of cosmic ray muon events. In contrast to the high resolution image obtained for charged particles, the TPC is not directly sensitive to neutrons, which contribute to reduce the visible energy in the neutrino and anti-neutrino measurements in DUNE. The neutrons can only be detected through high energy scattering or by thermal capture in argon. The capture signal is at the limit of the lowest energy considered for the DUNE neutrino program. A pulsed neutron calibration source is being developed for DUNE and will be tested in protoDUNE. This project is dedicated to the identification of neutrons in the protoDUNE data. The beam data will be used to measure the neutron multiplicity and associated invisible energy in proton-Argon interactions. The first data collected with the calibration source will provide a large sample of neutron captures, which will be used to extend the neutron tagging to signatures to lower energy neutrons. The work will include participation in the calibration data taking at CERN and prior tests needed for the development of the source.