Cloud chamber
Videos
A cloud chamber, also known as a Wilson chamber, is a particle detector used for visualizing the passage of ionizing radiation.
The original cloud chamber of C. T. R. Wilson at the Cavendish Lab, Cambridge, England.
Fig. 4: How condensation trails are formed in a diffusion cloud chamber.
Fig. 5: In a diffusion cloud chamber, a 5.3 MeV alpha-particle track from a Pb-210 pin source near Point (1) undergoes Rutherford scattering near Point (2), deflecting by angle theta of about 30 degrees. It scatters once again near Point (3), and finally comes to rest in the gas. The target nucleus in the chamber gas could have been a nitrogen, oxygen, carbon, or hydrogen nucleus. It received enough kinetic energy in the elastic collision to cause a short visible recoiling track near Point (2). (The scale is in centimeters.)
Example of watercooled thermoelectric cloud chamber
Carl David Anderson
Videos
Carl David Anderson was an American experimental physicist who shared the 1936 Nobel Prize in Physics with Victor Hess for his discovery of the positron, which confirmed the existence of antimatter.
Photo by Anderson of the first positron ever observed, 15 March 1933