Radio-detection of extensive air showers at the Pierre Auger Observatory - Results and enhancements

Abstract: The Pierre Auger Collaboration is exploring the potential of radio-detection techniques to measure the extensive air showers. The main advantage of these setups is the possibility to cover a large area with no atmospheric attenuation and having 100% duty cycle. Radio emission in the MHz range is recorded by the Auger Engineering Radio Array (AERA), presently consisting of 124 stations distributed over an area of approximately 6 km$^2$. This enhancement is focused on physics of cosmic rays with an energy greater than 10$^{17}$ eV. In addition, novel detection techniques based on the GHz emission from extensive air showers are being tested at the Pierre Auger Observatory. Three different setups are currently installed and are collecting data: MIDAS (Microwave Detection of Air Showers) and AMBER (Air-shower Microwave Bremsstrahlung Experimental Radiometer) are prototypes of an imaging parabolic dish detector, while EASIER (Extensive Air Shower Identification using Electron Radiometer) records the radio emission by antenna horns located on more than 60 surface detector units. The status of these different activities and the new results in MHz and GHz bands will be reported.