Radio signal and uncertainty estimation for the Radio Detector of the Pierre Auger Observatory

The Pierre Auger Observatory is the world’s largest experiment for hybrid detection of extensive air showers induced by high-energy cosmic rays. The Observatory is currently being upgraded to increase the sky coverage of mass-sensitive measurements of showers having zenith angles beyond 65∘ and energies up to 1020 eV. The design of this AugerPrime upgrade includes the deployment of the Radio Detector (RD), consisting of 1661 radio antennas installed on top of each of the water-Cherenkov detectors. Mass-composition studies of highly energetic and inclined showers will be possible by combining the electromagnetic energy estimated by the RD, and the estimation of the muon number obtained through the water-Cherenkov detector. The electromagnetic energy of the shower is proportional to the area integral of the energy deposit per unit area, also referred to as energy fluence. We will present a newly developed method for the reconstruction of the energy fluence, exploiting Rice distributions to determine radio signals and their uncertainties in the presence of noise. In the talk, the theoretical background employed in the new method and the improvements achieved in the energy fluence reconstruction in comparison to the previous approach will be discussed.