Abstract

The Deep Underground Neutrino Experiment (DUNE) utilizes Liquid Argon Time Projection Chamber (LArTPC) technology in its pursuit of uncovering the origins of matter. As a crucial prototype for the DUNE far detector (FD) module, ProtoDUNE-SP employs a hadron test beam with a momentum range of 0.3 to 7 GeV/c to study the detector response to particles that could be produced in the neutrino interactions at the DUNE FD . Neutral pion reconstruction performance is an important benchmark of the calorimetric and tracking capability of LArTPC and understanding neutral pion in LArTPC is crucial to characterise backgrounds to oscillation measurements and rare searches. To improve neutral pion reconstruction in LArTPC, a kinematic fitting algorithm was developed, achieving a 12% resolution in neutral pion energy in ProtoDUNE-SP. This improvement enables us to conduct the first measurements of the pion charge exchange differential cross-section. By comparing these results with the current model, valuable constraints can be made to improve generator simulations in future DUNE experiment.