Energy estimation for cosmic rays measured with the Auger Engineering Radio Array

The Auger Engineering Radio Array (AERA) is located within the Pierre Auger Observatory and currently consists of 24 self-triggered radio stations. Observation of radio signals from cosmic rays is confirmed by the surface detector (SD) stations of the Observatory which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For estimating the cosmic-ray energy we use the maximum absolute value of the measured electric field vector corrected for the incoming direction and the distance to the shower core. Performing a preliminary energy calibration using the SD information, we observe that the defined radio energy estimator provides an approximately linear dependency on the cosmic-ray energy.