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arXiv · 2507.04588

The Global Cosmic Ray Observatory -- Challenging next-generation multi-messenger astronomy with interdisciplinary research

Toshihiro Fujii
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Abstract

The origin of ultra-high-energy cosmic rays (UHECRs) is one of the most intriguing mysteries in astroparticle physics and high-energy physics. Since UHECRs with light mass compositions are less deflected by the Galactic and extragalactic magnetic fields, their arrival directions are more strongly correlated with their origins. Charged-particle astronomy with UHECRs is hence a potentially viable probe of extremely energetic phenomena in the universe. The Global Cosmic Ray Observatory (GCOS) is a proposed next-generation observatory to elucidate these origins through precise measurements of UHECRs with unprecedented exposure and mass identification capabilities. We will focus on the ideas and requirements for GCOS summarized in arXiv:2502.05657 and share the recent advances in detector developments and future perspectives with interdisciplinary research.

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Toshihiro Fujii. 2025-07-07. The Global Cosmic Ray Observatory -- Challenging next-generation multi-messenger astronomy with interdisciplinary research. https://arxiv.org/abs/2507.04588

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