Photodetector calibration and first calorimetric energy reconstruction of beam events from LAr scintillation light in ProtoDUNE-Single Phase experiment

ProtoDUNE Single Phase at CERN is the large scale prototype for the far detector of the future DUNE experiment. ProtroDUNE is in stable operation since Oct. 2018 at the CERN Neutrino Platform. Test beam data in the energy range of sub-GeV to a few GeV were collected in fall 2018 providing a set of key measurements. Particles (electrons, protons, pions, muons and kaons) are identified combining informations from a set of beam-line detectors (Time of Flight, Cherenkov) and TPC reconstruction. Three different photon collection technologies are utilized for the Photo Detector System modules. Each is designed to convert incident Liquid Argon scintillation photons (around 128 nm, in the Vacuum-UV range) into longer wavelength photons using photofluorescent compounds as wavelength shifters (WLS). Visible light is trapped within the module, a portion of which is eventually incident on an array of silicon photomultiplier photo-sensors. Each PD module has been fully characterized, providing calibration, single photo electron (SPE) response, signal-to-noise ratio (SNR), stability over time and photon detection eciency (PDE). Results of the protoDUNE-SP Photo Detector System response are presented, in particular with the Arapuca component, providing first calorimetric energy measurements and particle ID of beam events from LAr scintillation light signals.