The Cosmic Ray Extremely Distributed Observatory (CREDO)

The Cosmic Ray Extremely Distributed Observatory (CREDO) is a recently formed,global collaboration dedicated to observing and studying cosmic ray ensembles (CRE):groups of minimum two cosmic rays with common primary interaction vertex or thesame mother particle. The CREDO program embraces testing the known CRE scenarios,and getting ready to observe the unexpected physics, it is also suitable for multimessenger and multi-mission applications.

CRE could be formed both within classicalmodels (e.g. as products of photon-photon interactions), and exotic scenarios (e.g. asresults of decay of Super Heavy Dark Matter particles and subsequent interactions, Lorentz invariance violation), their fronts might be significantly extended in space andtime, and they might include cosmic rays of energies spanning the whole cosmic rayenergy spectrum.

CRE are expected to be partially observable on Earth even if theinitiating interaction or process occurs as far as ~1 Gpc away, with a footprintcomposed of at least two extensive air showers with parallel arrival directions andcorrelated arrival times. Since CRE are mostly expected to be spread over large areas over hundreds ofkilometers or more, and because of the expected wide energy range of thecontributing particles, CRE detection might only be feasible when using the availablecosmic ray infrastructure collectively, i.e. as a globally extended network of detectors.

CREDO is perfectly suited for probing the variation of fundamental constants in theaforementioned physical processes as well as for other applications like the search forsignatures of Earthquake precursors within the flux of cosmic rays.