#Antimatter be generated plus

These processes show a fundamental law of physics - that for each new lepton that is produced there is a corresponding new antilepton.Īlthough from a distance matter and antimatter would look essentially identical, there appears to be very little antimatter in our universe. In each reaction, one lepton and one antilepton is produced. Leptons are point-like particles that interact with the electromagnetic, weak and gravitational interaction, but not the strong interaction. The neutrino and electron are leptons while the antineutrino and positron are anti-leptons.

#Antimatter be generated plus

When 19Ne decays, a proton decays to a neutron plus a positron, e +, and an electron neutrino. When 14C decays, a neutron decays to a proton plus an electron and an electron antineutrino. When a proton and an antiproton annihilate at rest, other particles are usually produced, but the total kinetic plus rest mass energies of these products adds up to twice the rest mass energy of the proton (2 x 938 MeV).Īntimatter is also produced in some radioactive decays. The annihilation of positrons and electrons is the basis of Positron Emission Tomography (PET) discussed in the section on Applications (Chapter 14). These gamma rays go off in opposite directions because both energy and momentum must be conserved. For example, when an electron and a positron annihilate at rest, two gamma rays, each with energy 511 keV, are produced. This result gave credibility to the idea that for every particle there is a corresponding antiparticle.Ī particle and its antimatter particle annihilate when they meet: they disappear and their kinetic plus rest-mass energy is converted into other particles (E = mc 2). Occasionally, the energy brought into the collision would produce a proton-antiproton pair in addition to the original two protons. In order to create the anti-proton, protons were accelerated to very high energy and then smashed into a target containing other protons. In the 1950's, physicists at the Lawrence Radiation Laboratory used the Bevatron accelerator to produce the anti-proton, that is a particle with the same mass and spin as the proton, but with negative charge and opposite magnetic moment to that of the proton. We know that the particle Anderson detected was the anti-electron predicted by Dirac.

He named this positive electron a positron. One particle made a track like an electron, but the curvature of its path in the magnetic field showed that it was positively charged.

In 1932, Carl Anderson, was examining tracks produced by cosmic rays in a cloud chamber. This antielectron would be expected to have the same mass as the electron, but opposite electric charge and magnetic moment. One of the remarkable predictions of this theory was that an anti-particle of the electron should exist. In 1930, Paul Dirac developed the first description of the electron that was consistent with both quantum mechanics and special relativity.