Feasibility of VHE gamma ray detection by an array of imaging atmospheric Cherenkov telescopes using the fluorescence technique

TL;DR

This paper explores the potential of using fluorescence detection with Cherenkov telescopes, specifically the CTA, to observe ultra-high-energy gamma rays, offering a promising extension to current detection methods.

Contribution

It proposes a novel technique combining fluorescence detection with Cherenkov telescopes, leveraging existing hardware with minimal modifications for ultra-high-energy gamma ray observation.

Findings

Feasibility of fluorescence detection with CTA hardware.

Potential to extend gamma ray energy range beyond current limits.

Complementary to existing Cherenkov detection methods.

Abstract

The last 20 years have seen the development of new techniques in Astroparticle Physics providing access to the highest end of the electromagnetic spectrum. It has been shown that some sources emit photons up to energies close to 100 TeV. Yet the fluxes of these photons are incredibly low and new detection techniques are needed to go higher in energy. A new technique that would use the new generation of Cherenkov Telescopes, i.e., the Cherenkov Telescope Array (CTA), is proposed to push further the energy frontier. It is based on the detection of the fluorescence radiation emitted in extensive air showers, a successful method used in ultra-high-energy cosmic ray experiments, like the Pierre Auger Observatory. It would complement the standard imaging atmospheric Cherenkov technique with only minor modifications of the hardware currently being developed for the CTA and would not imply significant extra costs during its planned operation.