UC Berkeley

Studies of fundamental interactions have played a principle role in the development of our understanding of particle physics, but the \ac{SM} remains incomplete.The phenomenon of neutrino oscillation lies outside of the prescriptions of the \ac{SM}, driving current experimental efforts. The \acf{DUNE} is being built to provide a comprehensive study of neutrino oscillation and to search for \ac{BSM} physics. To accomplish this, \ac{DUNE} utilizes a massive-scale far detector, a sophisticated near detector, and a high-intensity, broad-spectrum neutrino beam. The near detector adopts a new design of \ac{LArTPC} with pixelated charge readout and a modular structure to resolve events in the high-intensity neutrino beam. A prototype of this detector design was successfully operated at the University of Bern, Switzerland in 2021. From the cosmic-ray data collected with this prototype, a study of muon capture on argon has been performed, resulting in the first measurement of the Huff factor for argon ($R_H = 1.29 \pm 0.15$) and measurements of the muon capture rate ($\lambda_c = 1.53\pm0.19~\mu$s$^{-1}$) and muon disappearance rate ($\lambda_d = 2.11\pm0.24~\mu$s$^{-1}$) in argon. These results can help to reduce the uncertainty in neutrino-nucleus cross-section modelling at low $Q^2$.