Proton Multiplicity Measurement using the ProtoDUNE-SP Detector

The upcoming DUNE long baseline neutrino oscillation experiment will utilize a liquid argon (total ~70 kton) time projection chamber to measure neutrino oscillation parameters. Understanding pion-argon interactions is important to correctly interpreting future data from experiments such as DUNE, as well as for improving current event generators and models used in simulations. Measuring the number of final state protons in pion-argon interactions will help further our understanding of these interactions. By analyzing data from Monte Carlo simulations, appropriate selection criteria for these final state protons and pions were determined, as well as the expected purity and efficiency of this selection. Using 1 GeV data from the 770 ton ProtoDUNE-SP detector, the number of such particles was then measured. The dependence of this distribution on the incident pion energy and whether final state pions were detected was also studied. The results of this analysis on ProtoDUNE-SP data will be presented and compared with expectations from the simulated data.