Search for Extensive Photon Cascades with the Cosmic-Ray Extremely Distributed Observatory

TL;DR

This paper discusses the potential of the Cosmic-Ray Extremely Distributed Observatory (CREDO) to detect extensive photon cascades from astrophysical sources, which could reveal new insights into cosmic photon phenomena beyond traditional single-photon detection methods.

Contribution

It introduces CREDO's novel approach to detecting photon cascades over large distances, expanding the scope of cosmic photon studies beyond existing gamma-ray and cosmic ray observatories.

Findings

CREDO aims to detect photon cascades using a dense array of detectors.

Photon cascades can produce unique air shower patterns observable on Earth.

Detecting low-energy, widely spaced air showers can reveal cascade phenomena.

Abstract

Although the photon structure is most efficiently studied with the accelerator instruments, there is also a scientifically complementary potential in investigations on photons produced in the outer space. This potential is already being explored with gamma ray telescopes, ultra-high energy cosmic ray observatories and, since very recently, by the Cosmic-Ray Extremely Distributed Observatory (CREDO). Unlike the former instruments focused on detection of single photons, CREDO aims at the detection of cascades (ensembles) of photons originating even at astrophysical distances. If at least a part of such a cascade reaches Earth, it might produce a unique pattern composed of a number of air showers observable by an appropriately dense array of standard detectors. If the energies of air showers constituting the pattern are relatively low and if the typical distances between the neighbors are large, the ensemble character of the whole phenomenon might remain uncovered, unless the CREDO strategy is implemented.