Michel Electron Reconstruction Using Cosmic-Ray Data from the MicroBooNE LArTPC

The MicroBooNE liquid argon time projection chamber(LArTPC) has been taking data at Fermilab since 2015 collecting, in addition to neutrino beam, cosmic-ray muons. Results are presented on the reconstruction of Michel electronsproduced by the decay at rest of cosmic-ray muons. Michel electronsare abundantly produced in the TPC, and given their well known energy spectrum can be used to study MicroBooNE's detector response to low-energy electrons( electronswith energies up to ~50 MeV). We describe the fully-automated algorithm developed to reconstruct Michel electrons, with which a sample of ~14,000 Michel electroncandidates is obtained. Most of this article is dedicated to studying the impact of radiative photons produced by Michel electronson the accuracy and resolution of their energy measurement. In this energy range, ionization and bremsstrahlung photon production contribute similarly to electronenergy loss in argon, leading to a complex electrontopology in the TPC. By profiling the performance of the reconstruction algorithm on simulation we show that the ability to identify and include energy deposited by radiative photons leads to a significant improvement in the energy measurement of low-energy electrons. The fractional energy resolution we measure improves from over 30% to ~20% when we attempt to include radiative photons in the reconstruction. These studies are relevant to a large number of analyses which aim to study neutrinos by measuring electronsproduced by $\nu_e$ interactions over a broad energy range.