On the prospects of ultra-high energy cosmic rays detection by high altitude antennas

TL;DR

This paper evaluates the potential of high-altitude antennas, including satellite-based systems, for detecting ultra-high energy cosmic rays via radio signals reflected off ice, suggesting satellites could significantly outperform existing observatories.

Contribution

The study provides an exposure estimate for high-altitude antennas, highlighting the promising prospects of satellite-based detection of UHECRs compared to other methods.

Findings

Satellite antennas may achieve larger exposure than current observatories.

Balloon-borne and mountaintop antennas are less competitive.

Further experimental characterization of reflected radio signals is needed.

Abstract

Radio emission from Ultra-High Energy Cosmic Rays (UHECR) showers detected after specular reflection off the Antarctic ice surface has been recently demonstrated by the ANITA balloon-borne experiment. An antenna observing a large area of ice or water from a mountaintop, a balloon or a satellite may be competitive with more conventional techniques. We present an estimate of the exposure of a high altitude antenna, which provides insight on the prospects of this technique for UHECR detection. We find that a satellite antenna may reach a significantly larger exposure than existing UHECR observatories, but an experimental characterization of the radio reflected signal is required to establish the potential of this approach. A balloon-borne or a mountaintop antenna are found not to be competitive under any circumstances.