Carl David Anderson

Charles Anderson was born in 1905 in New York, in 1927 he graduated from the California Institute of Technology.

. The main focus of Anderson's research on X-ray and gamma-rays, cosmic ray physics, elementary particle physics.

. The most significant discovery Anderson was the experimental discovery of the positron in cosmic rays
. Anderson with the assistance of Millikan built a special cloud chamber and placed it in a very strong magnetic field. Such a device allowed to observe and to photograph the tracks of charged particles, the intensity of the track to judge the mass of the particle and the direction of deviation of the track in a magnetic field - the sign of the charge particles.

There have been hundreds of pictures. Truly historic picture has received 2 August 1932, Mr.. For the first time before "photograph of" positron - the traces left by a particle moving upward. By the nature of deviations in the magnetic field it was evident that the particle has a positive charge and can not be identified with the proton.
After that, Anderson has studied more than 1300 photos. In 15 of them were "visible positive particles passing through the lead, neither of which could have just as much mass as the proton mass,. It is suggested that Anderson called positive electron positron, and the term immediately went into scientific use. He also wanted to enter the name negatrons for the negative electron. In this case, his proposal had no success.

For the theory of the structure of matter detection of the positron was essential. Turned, . that the energy in the form of cosmic rays or gamma rays, under appropriate conditions can be transformed into a pair of particles (in 1933, Carl Anderson, independently of the others discovered the phenomenon of electron-positron pairs from gamma-quantum) and, . opposite, ,
. This finding was of fundamental importance in connection with the fundamental principle of equivalence of energy and mass.

Carl Anderson was awarded half the Nobel Prize in Physics in 1936 with the shorthand expression "for the discovery of the positron". The second half was given to Victor Hess ( "for the discovery of cosmic rays") - the man who discovered the first of these rays, and thus gave scientists a new object of research leading to many unexpected discoveries.
. Continuing his studies, Anderson in 1938, with S. sovmenstno Neddermeyerom opened another new elementary particles - the muon, and determined its mass.

. Interestingly, the history of discovery of the positron by Anderson is an example of a successful chance in science
. Sam Anderson recalled: "The discovery of the positron was completely random, although the relativistic Dirac's theory also predicts, and its existence. The purpose of the experiment, which led to the discovery, was simply to measure the energy spectrum of secondary electrons produced in the atmosphere and other materials due to the incoming radiation from space. "