Event Generators at Colliders and Beyond Colliders

28 July - 22 August 2025

Simon Plätzer, Leif Lönnblad, Anita Reimer, Stefan Söldner-Rembold, Laura Fabbietti

Event generators are sophisticated simulation packages that describe particle reactions at high energies. They are indispensable tools to design and interpret the experiments that teach us about the fundamental constituents of matter and their interactions. Besides their prominent role at manmade colliders, event generators are equally important to simulate the physics of cosmic rays, both in their origin and signatures on Earth, and the signature of physics beyond the Standard Model (SM) in the next-generation neutrino experiments. In light of such applications and the opportunities to discover New Physics at both Earth-bound reactions and those reactions of cosmic origin, creating a forum for exchange between the different communities has become crucial. The core aim of the proposed workshop is thus to spark this much-needed exchange between developers and users of event generators of the various science communities to improve our understanding of phenomenological models and the accuracy of different simulation components across vastly different energy scales. This is needed for precision predictions at colliders and the use of cutting-edge methods for discoveries using cosmic rays, neutrino, and gamma-ray experiments. The workshop will make a first step towards this goal by evaluating demands on the simulations and by establishing interoperability between different models and components to build a sustainable community effort for particle physics simulations in Earth-bound and astrophysics environments. This proposal therefore is, at first sight, necessarily broad in its nature as are the types of reactions which event generators are able to describe. However, the presence of different communities is vital to build the bridges we envisage.



Topical Structure

Topic 1 – Hadronization across different energies

Topic 2 – Dense environments and nuclear reactions

Topic 3 – interactions with photons and neutrinos

Topic 4 – backbone infrastructure and validation