# Overview of lunar detection of ultra-high energy particles and new plans for the SKA

## TL;DR

This paper reviews the lunar detection technique for ultra-high-energy particles, discusses recent advances, and outlines plans for integrating this method into the upcoming SKA-low radio telescope array to enhance detection capabilities.

## Contribution

It provides a comprehensive overview of lunar particle detection, highlights technical challenges, and proposes a roadmap for incorporating this method into SKA-low observations for UHE particle detection.

## Key findings

- SKA-low is predicted to detect unprecedented UHE cosmic rays.
- Technical challenges include detecting nanosecond pulses with large radio arrays.
- Sensitivity estimates for SKA phases 1 and 2 are provided.

## Abstract

The lunar technique is a method for maximising the collection area for ultra-high-energy (UHE) cosmic ray and neutrino searches. The method uses either ground-based radio telescopes or lunar orbiters to search for Askaryan emission from particles cascading near the lunar surface. While experiments using the technique have made important advances in the detection of nanosecond-scale pulses, only at the very highest energies has the lunar technique achieved competitive limits. This is expected to change with the advent of the Square Kilometre Array (SKA), the low-frequency component of which (SKA-low) is predicted to be able to detect an unprecedented number of UHE cosmic rays. In this contribution, the status of lunar particle detection is reviewed, with particular attention paid to outstanding theoretical questions, and the technical challenges of using a giant radio array to search for nanosecond pulses. The activities of SKA's High Energy Cosmic Particles Focus Group are described, as is a roadmap by which this group plans to incorporate this detection mode into SKA-low observations. Estimates for the sensitivity of SKA-low phases 1 and 2 to UHE particles are given, along with the achievable science goals with each stage. Prospects for near-future observations with other instruments are also described.