Solar System objects as cosmic rays detectors

TL;DR

This paper critically evaluates the idea of using Solar System objects like Jupiter as detectors for ultra-high energy cosmic rays, concluding that such methods are ineffective or less competitive than existing ground-based detectors.

Contribution

It corrects previous assumptions about Jupiter's effectiveness as a UHECR detector and assesses other Solar System objects for similar detection potential.

Findings

Jupiter is not an efficient UHECR detector due to incorrect assumptions.

Other Solar System objects are not suitable or competitive for UHECR detection.

The proposed space-based detection method is generally not viable.

Abstract

In a recent Letter (Rimmer et al. 2014), Jupiter is presented as an efficient detector for Ultra-High Energy Cosmic Rays (UHECRs), through measurement by an Earth-orbiting satellite of gamma rays from UHECRs showers produced in Jupiter's atmosphere. We show that this result is incorrect, due to erroneous assumptions on the angular distribution of shower particles. We evaluated other Solar System objects as potential targets for UHECRs detection, and found that the proposed technique is either not viable or not competitive with traditional ground-based UHECRs detectors.