A Monte Carlo framework for the simulation of particle showers initiated in the Earth's atmosphere (or dense media) by high-energy particles from the cosmos.
In astroparticle physics, we study high-energy particles arriving from the cosmos at the Earth. These can be charged atomic nuclei (so-called "cosmic rays"), photons, leptons or only weakly-interacting neutrinos. When these particles interact in the Earth's atmosphere or in dense media, they initiate particle cascades that can grow to billions of particles before the so-called "particle shower" is finally absorbed through ionization of the interaction medium.
The simulation of particle showers is a problem of a highly statistical nature, best addressed by a Monte Carlo approach. A very diverse set of processes such as particle interactions, particle propagation and decay need to be treated with high accuracy over a vast parameter space. As these particles can have energies way beyond those reachable by human-made accelerators, also the interaction physics is not fully known, so that a number of different interaction models exist which need to be interchangeable. Electromagnetic emissions from these particle showers, for example optical Cherenkov light or radio waves, can also be calculated in the simulations.
The CORSIKA code, developed and maintained at Karlsruhe Institute of Technology, has been the work horse for particle-shower simulations in the astroparticle physics community for over 30 years. It is being used by numerous projects aiming at the detection of charged cosmic rays, photons or neutrinos worldwide. Version 7 of the code is based on FORTRAN and is still under active development and maintenance. In parallel, a complete rewrite of the functionality in a modern C++ framework is ongoing and will be released as Version 8 of the code.
The air shower simulation program CORSIKA is crucial for the planning, construction, operation and success of the Cherenkov Telescope Observatory (CTAO).
CORSIKA has been a mainstay for the detailed understanding of the physics of high energy extensive air showers for many years, and its wide use in our community has provided clear and compelling synergies with many experimental cosmic ray efforts.
CORSIKA has been the tool for simulating air showers for the Pierre Auger Observatory from the very beginning of the project more than 20 years ago. The high quality of the code and the continuous development and maintenance of it have been absolutely fundamental for the success of the Pierre Auger Observatory.
CORSIKA is since several decades the de-facto standard for air shower simulations in the field.
The CORSIKA project has served as a bright and reliable beacon in the rough seas of the cosmic ray field.
As a member of the astroparticle physics community and elected spokesperson of the Pacific Ocean Neutrino Experiment (P-ONE), I can attest to the vital role that CORSIKA plays in our research.
From the beginning of the project, we have relied exclusively on CORSIKA for our air-shower simulations, as the de facto standard in our field.
The HAWC collaboration has always been an intense user of the existing CORSIKA 7 simulation program to generate the simulated gamma and hadron showers in our simulation and analysis chain.
IceCube-Gen2 strongly relies on precise simulations of particle showers for its research. In particular, the background to the detection of high-energy neutrinos posed by muons and muon neutrinos arising from extensive air showers needs to be determined accurately, for which simulations with CORSIKA 7 are being used extensively.
Using CORSIKA allows for various systematic uncertainty studies related to the atmospheric density, the magnetic field, the hadronic interaction models, and the primary flux itself.
With of the order of 100,000 CPU hours expended per year, the simulations generated by the CORSIKA software package form the fundamental basis for the analysis of the recorded data, and thus MAGIC’s scientific productivity.
CORSIKA, as a general, reliable and widely applied tool for EAS simulation, is heavily used in LHAASO experiment for its design and data analysis.
CORSIKA has been one of the most important work horses in the field of air shower physics for decades.
Air showers and their remnants as entering the ice are an important background signal for our detector. We have been relying and will rely heavily on CORSIKA simulations.
Accurate and detailed air-shower simulations are required for the calculation of the instrument response of VERITAS. The CORSIKA code has been used for many years for this task and it has been (and will be) absolutely crucial for every single scientific result of the VERITAS Collaboration.