dule-0: first operation of the modular DUNE LAr Near Detector prototype LArTPC

Abstract:
The Deep Underground Neutrino Experiment (DUNE) is a next generation long-baseline neutrino oscillation experiment designed to resolve the neutrino mass hierarchy to 5σ precision in the near-term and after a 10 year exposure observe charge-parity violation in the neutrino sector to a precision of 5σ for 50% of all δCP values. A performant near detector is critical for reducing systematic uncertainties in order to realize DUNE neutrino oscillation physics sensitivities. With optical segmentation and high photodetector coverage, the liquid argon time projection chamber component (ND-LAr) of the DUNE Near Detector complex is designed to be resilient to the 55 neutrino interactions per beam spill expected from the intense LBNF neutrino beam. In addition, the expected beam neutrino pile-up at ND-LAr necessitates pixelated charge readout that eliminates the ambiguities common to projective wire or strip charge readout. Furthermore, unambiguous 3D charge information facilitates accurate time-tagging and thereby association to the correct neutrino interaction. LArPix incorporates low-power 64-channel custom ASICs with a mixed-signal large-format printed circuit board for an unambiguous 3D charge-readout. Here I focus on the operation of the first modular ND-LAr prototype (Module-0) with emphasis on LArPix performance evaluation.