Emulsion photograph showing the tracks of various cosmic ray nuclei, ranging from a hydrogen nucleus to an iron nucleus. The more protons a nucleus co

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Emulsion photograph showing the tracks of various cosmic ray nuclei, ranging from a hydrogen nucleus to an iron nucleus. The more protons a nucleus contains, the higher its positive electric charge & the greater its ability to ionise; the more it ionises, the denser its track in emulsion. Hydrog- en has 1 proton & produces a barely visible track. Ionisation depends on the square of the charge; so lithium's 3 protons have 9 times hydrogen's charge & produce a track 9 times denser. Iron, with 26 protons, produces a track 676 times denser than hydrogen. The wispy strands that adorn the denser tracks are \delta rays\" - electrons knocked out of atoms in the emulsion by the passing nucleus."

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Size: 5052px × 3381px
Photo credit: © POWELL FOWLER PERKINS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: atomic, black, black--white, charge, cosmic, electric, emulsion, high-energy, image, mass, monochrome, nuclear, nuclei, nucleus, odyssey, particle, photo, photograph, physics, primary, ray, white