Detection of ultra-high energy cosmic ray showers with a single-pixel fluorescence telescope

TL;DR

This paper introduces a novel, cost-effective large-area fluorescence detector array for ultra-high energy cosmic rays, demonstrating its operational stability and initial detection capabilities with a prototype system.

Contribution

It proposes a new single-pixel fluorescence telescope design for UHECR detection and reports initial successful observations and stability tests at the Telescope Array site.

Findings

Detected laser shots at several kilometers distance

Identified 16 significant UHECR shower candidates

Demonstrated operational stability over 19 nights

Abstract

We present a concept for large-area, low-cost detection of ultra-high energy cosmic rays (UHECRs) with a Fluorescence detector Array of Single-pixel Telescopes (FAST), addressing the requirements for the next generation of UHECR experiments. In the FAST design, a large field of view is covered by a few pixels at the focal plane of a mirror or Fresnel lens. We report first results of a FAST prototype installed at the Telescope Array site, consisting of a single 200 mm photomultiplier tube at the focal plane of a 1 m$^2$ Fresnel lens system taken from the prototype of the JEM-EUSO experiment. The FAST prototype took data for 19 nights, demonstrating remarkable operational stability. We detected laser shots at distances of several kilometres as well as 16 highly significant UHECR shower candidates.