Physicists zoom into the birth of cosmic rainstorms with new CERN study

Scientists are eager to delve deeper into the nature of cosmic rays that generate particle showers in Earth's atmosphere. Every second, particles traverse your body at speeds nearing light, descending from a sky-high cosmic storm where these rays, a potent form of extraterrestrial matter, incessantly collide with atoms. Though researchers have been observing these cosmic rainstorms for over a century, their formation remains shrouded in mystery.

To unravel this enigma, scientists have turned to a specialized tool: CERN's Large Hadron Collider in Switzerland.

In collaboration with a team of particle physicists, the author of this study employed the world's inaugural laboratory collisions of oxygen atoms with protons to replicate cosmic rays in the lab. Their findings have recently been published in Physical Review Letters. When a cosmic ray collides with a nucleus in Earth's atmosphere, it sparks a cascade of particles.

This concept was first introduced by physicist Victor Hess in the early 20th century, who discovered cosmic rays using hot air balloons. Hess's discovery earned him the 1936 Nobel Prize in physics.

Interestingly, experiments later revealed that cosmic radiation also harbors new forms of matter, known as antimatter, comprising elusive particles like muons, pions, and kaons. These constituents, akin to electrons, protons, and neutrons found within atoms, are transient and more challenging to detect. Understanding these components has significantly contributed to the formulation of contemporary particle physics theories.

Despite substantial progress, several questions persist. The origins of cosmic rays remain unclear, as does the mechanism by which they achieve such high energies. Researchers are gradually piecing together evidence pointing to cosmic rays emanating from extremely hot and distant regions of the universe, possibly ejected by exploding stars or supermassive black holes. The Crab Nebula, the aftermath of an exploded star, is believed to be one such source.