The antiproton (aka pbar) is the antiparticle of the proton. Antiprotons are short-lived in nature, since any collision with a proton will cause both particles to be annihilated in a burst of energy. It was discovered in the year 1955 by University of California Berkeley Physicists Emilio Segre and Owen Chamberlain, for which they were awarded a 1959 Nobel Prize in Physics. Pbar is a common way of referring to an antiproton. ... Corresponding to each kind of particle, there is an associated antiparticle with the same mass and spin. ... Properties In physics, the proton (Greek proton = first) is a subatomic particle with an electric charge of one positive fundamental unit (1. ... Annihilation is defined as total destruction or complete obliteration of a particular object. ... 1955 (MCMLV) was a common year starting on Saturday of the Gregorian calendar. ... Emilio Gino Segr (February 1, 1905 - April 22, 1989) was an Italian American physicist who, with Owen Chamberlain, won the 1959 Nobel Prize in Physics for their discovery of the antiproton. ... Owen Chamberlain (b. ... 1959 (MCMLIX) was a common year starting on Thursday of the Gregorian calendar. ... Hannes Alfvén, 1970 winner for work on astrophysical plasmas List of Nobel Prize laureates in Physics from 1901 to the present day. ...

Their formation requires energy equivalent to a temperature of 10 million °C, and Big Bangs aside, this does not tend to happen naturally. However, at CERN, protons are accelerated in the Proton Synchrotron (PS) to an energy of 26 GeV, and then smashed into an iridium rod. The protons bounce off the iridium nuclei with enough energy for matter to be created. A range of particles and antiparticles are formed, and the antiprotons are separated off using magnets. According to the Big Bang theory, the universe originated in an extremely dense and hot state (bottom). ... CERN logo CERN is the European Council for Nuclear Research (Organisation Européenne pour la Recherche Nucléaire), the worlds largest particle physics laboratory, situated on the border between France and Switzerland, just west of Geneva. ... A synchrotron is a particular type of cyclic particle accelerator in which the magnetic field (to turn the particles so they circulate) and the electric field (to accelerate the particles) are carefully synchronized with the travelling particle beam. ... General Name, Symbol, Number iridium, Ir, 77 Chemical series transition metals Group, Period, Block 9, 6, d Appearance silvery white Atomic mass 192. ... Corresponding to each kind of particle, there is an associated antiparticle with the same mass and spin. ...

See also

• Antimatter
• Antineutron
• List of particles