Speaker
Description
To probe the sources of ultra-high energy cosmic-rays, next generation of radio experiments such as GRAND and AugerPrime Radio are now focusing on the detection of showers arriving with very inclined trajectories. These inclined showers have a large footprint that allows us to cover large surfaces at low costs, but their radio emission exhibits numerous features that differentiate them from vertical ones. Yet, further studies are needed to fully characterize their complex radio emission. Using Monte-Carlo simulations we evidence here 2 major novel features of these inclined showers: a significant drop of more than one order of magnitude in the geomagnetic emission amplitude and a new polarization pattern. The latter possibly indicates a synchrotron emission taking over the Askaryan at large zenith angles. These two effects are challenging to describe with existing models of the radio emission but could strongly affect the detection and reconstruction strategies of next generation experiments. In this talk I will present our main results toward the understanding of these new features.
