A new method for calibration of the DUNE Liquid Argon Near Detector

The Deep Underground Neutrino Experiment will begin an era of precision physics as it seeks to measure the CP violation in the lepton sector, search for astrophysical neutrinos and look for proton decay. The Near Detector will play a crucial role in reducing the systematic uncertainties related to the neutrino flux and meet the 1% energy resolution targeted by the experiment.

We describe an in-situ method to calibrate the liquid argon Near Detector with electrons emitted from photocathode sources placed on the cathode plane of the liquid argon time projection chamber (LArTPC) detector. These photocathode sources are illuminated by optic fibers terminating at the anode plane which bring in UV light from a high-power laser outside the cryostat. The method is envisioned to provide precise energy calibration by controlling the light input and thus the photo-electron emission in the detector.