Observing Ultra-High Energy Cosmic Rays with Smartphones

TL;DR

This paper proposes using a global network of smartphones as a cost-effective, large-scale detector array to observe ultra-high energy cosmic rays through their air shower signatures.

Contribution

It introduces a novel method of repurposing smartphones as a distributed detector network for ultra-high energy cosmic rays, leveraging their CMOS sensors.

Findings

Potential for significant observation power at highest energies

Large-scale smartphone network can compensate for small sensor size

Feasibility depends on user adoption levels

Abstract

We propose a novel approach for observing cosmic rays at ultra-high energy ($>10^{18}$~eV) by repurposing the existing network of smartphones as a ground detector array. Extensive air showers generated by cosmic rays produce muons and high-energy photons, which can be detected by the CMOS sensors of smartphone cameras. The small size and low efficiency of each sensor is compensated by the large number of active phones. We show that if user adoption targets are met, such a network will have significant observing power at the highest energies.