extensive air shower
Quick Summary
An extensive air shower (EAS) is a phenomenon in physics that occurs when very high-energy cosmic rays interact with Earth's atmosphere. These cosmic rays, which are high-speed particles originating from space, collide with atmospheric nuclei. This collision generates a cascade of secondary particles, including photons, electrons, and muons, spreading out over large areas.1
These showers are not directly observed but are detected by arrays of particle detectors on the ground. The study of EAS is crucial for understanding the nature and origin of the most energetic cosmic rays, which can have energies comparable to a thrown baseball. While most cosmic rays come from within our galaxy, the highest-energy particles are thought to originate from beyond the Milky Way.1
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