Dune Experiment

The next generation of long-baseline neutrino experiments have as primary physics goals the observation of neutrino and antineutrino oscillation patterns to precisely measure the parameters governing long-baseline neutrino oscillation, and to test the three-flavor paradigm. The demonstration of the leptonic CP violation will be an important step towards the leptogenesis mechanism as an explanation of the observed baryon asymmetry in the Universe. While the present generation of neutrino experiments, such as T2K and NOvA, will start providing the first hints of the existence of CP violation and some sensitivity to the mass ordering, they will not be able to provide a significant enough measurement.

The long-baseline Deep Underground Neutrino Experiment (DUNE) is a planned dual-site neutrino experiment. This experiment will study high-energy neutrinos from a new, high-intensity wide-band neutrino beam (LBNF) generated by a megawatt-class proton accelerator at Fermilab, after traveling a distance of 1300 km to a far detector located deep underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota. The requirement to cleanly reconstruct multi-GeV neutrino interactions dictates the choice of the liquid argon time projection chamber (LArTPC) technology as the optimal one for DUNE. The far detector will be composed of four large LArTPC detectors of 17-kt each. DUNE considers different LArTPC technologies for the far detectors. The project is completed with a highly-capable near detector placed very close to the beam.

The combination of a massive fine-grained detector and underground detector placement also allows DUNE to have broad discovery potential beyond the accelerator neutrino program. DUNE will perform Beyond the Standard Model searches, for instance, the observation of nucleon decay would be a watershed event for the understanding of physics at high energy scales. Neutrinos from supernovae would provide key insights into the physics of gravitational collapse and may also reveal fundamental properties of the neutrino.

CIEMAT (I. Gil) is DUNE Physics Coordinator and (C. Cuesta) co-convenor of the Low Energy Neutrino Physics Working Group. CIEMAT developed simulations to study the DUNE supernova burst triggering efficiency showing that nearly 100% efficiency is possible out to the edge of the galaxy, and 70% efficiency for a burst at the Large Magellanic Cloud [EPJC 81 (2021) 423, PhD Thesis A.Gallego]. 

The FD modules will be built 1.5 km below ground at the SURF facility so that our measurements are less affected by cosmic radiation. As planned, the first FD module will employ Horizontal Drift (HD) technology, and the second module will have Vertical Drift (VD). The third and forth FD modules will employ a technology to be defined. We are working at CIEMAT on the Photon Detection System design optimization and procurement for the Far Detector modules.