Measurement of neutral current single π 0 production on argon with the MicroBooNE detector

Abstract

We report the first measurement of π 0 production in neutral current (NC) interactions on argon with average neutrino energy of ≲ 1

GeV . We use data from the MicroBooNE detector’s 85 metric tons active volume liquid argon time projection chamber situated in Fermilab’s Booster Neutrino Beam and exposed to 5.89 × 10 20 protons on target for this measurement. Measurements of NC π 0 events are reported for two exclusive event topologies without charged pions. Those include a topology with two photons from the decay of the π 0 and one proton and a topology with two photons and zero protons. Flux-averaged cross sections for each exclusive topology and for their semi-inclusive combination are extracted (efficiency correcting for two-plus proton final states), and the results are compared to predictions from the genie, neut, and nuwro neutrino event generators. We measure cross sections of 1.243 ± 0.185 ( syst ) ± 0.076 ( stat ) , 0.444 ± 0.098 ± 0.047 , and 0.624 ± 0.131 ± 0.075

[ 10 − 38

cm 2 / Ar ] for the semi-inclusive NC π 0 , exclusive NC π 0 + 1 p , and exclusive NC π 0 + 0 p processes, respectively.