Welcome to the 40th International Cosmic Ray Conference (ICRC2027), to be held from July 20–29, 2027, in Buenos Aires, Argentina, at the Universidad Católica Argentina (UCA).

Since its first edition in 1947, the International Cosmic Ray Conference has served as the leading biennial meeting of the global astroparticle physics community. Organized under the auspices of Commission C4 of the International Union of Pure and Applied Physics (IUPAP), the conference brings together researchers from universities, observatories, and laboratories worldwide to present and discuss the latest developments in cosmic ray physics, high-energy and gamma-ray astrophysics, neutrino astrophysics, dark matter, solar and heliospheric physics, multi-messenger astronomy, gravitational waves, and related instrumentation and data analysis.

ICRC2027 will be the first edition of the conference to be held in Argentina and only the fourth to take place in Latin America. Argentina has a long-standing tradition of research in particle physics, astrophysics, and cosmology, with a strong network of universities and research institutions and active participation in major international collaborations. The country is also home to the Pierre Auger Observatory, the world’s largest observatory for the detection of astroparticles. All of this makes Buenos Aires the ideal setting for this historic edition of the conference.

The Local Organizing Committee looks forward to welcoming participants from around the world for ten days of scientific exchange, collaboration, and discovery. We hope ICRC2027 will inspire new ideas, foster lasting international partnerships, and become a memorable chapter in the history of the International Cosmic Ray Conference.