J/psi particle


J/psi particle
/jay"suy", -psuy"/, Physics.
the lightest of the psi particles, the first particle to be discovered that contains a charmed quark.
[1975-80; see J PARTICLE, PSI PARTICLE]

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      type of meson consisting of a charmed quark and a charmed antiquark. It has a mass of 3.1 GeV/c2, which is about 3.5 times larger than the mass of a proton. The particle was first detected in 1974 by two groups of American physicists working independently of each other, one headed by Burton Richter at SLAC (Stanford Linear Accelerator Center) in Menlo Park, Calif., and another headed by Samuel Ting at the Brookhaven National Laboratory in Upton, Long Island, N.Y. The discovery of the J/psi shed new light on quarks (quark) and their interactions. It provided support for the theory that there existed a fourth quark, called the charmed quark, in addition to those predicted by early quark models (i.e., the up, down, and strange quarks). See also meson.

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Universalium. 2010.

Look at other dictionaries:

  • psi particle — n. Particle Physics J PARTICLE …   English World dictionary

  • psi particle — noun a neutral meson with a large mass • Syn: ↑J particle • Hypernyms: ↑meson, ↑mesotron * * * noun see psi II * * * /suy, psuy/, Physics. 1. any of a family of mesons consisting of a charmed …   Useful english dictionary

  • psi particle — noun Date: 1974 J/psi particle …   New Collegiate Dictionary

  • psi particle — /suy, psuy/, Physics. 1. any of a family of mesons consisting of a charmed quark and a charmed antiquark. 2. an early name for the J/psi particle. [1970 75] * * * …   Universalium

  • psi particle — /ˈsaɪ patəkəl/ (say suy pahtuhkuhl) noun a type of meson characterised by charm (charm1 def. 9). Also, J particle. {psi (def. 1) + particle (def. 2) …   Australian English dictionary

  • j/psi particle — ˈjāˈsī noun Usage: usually capitalized J : an unstable neutral fundamental particle of the meson family that has a mass about 6000 times the mass of an electron, has an unusually long lifetime, and is thought to consist of a charmed quark and… …   Useful english dictionary

  • J/psi particle — noun Date: 1977 an unstable neutral fundamental particle of the meson group that has a mass about 6000 times the mass of an electron called also J particle, J/psi, psi particle …   New Collegiate Dictionary

  • J/psi particle — noun a subatomic particle with an unusually long lifetime and a large mass; a bound state of a charm quark and a anti charm quark Syn: J/psi meson, J/ψ particle …   Wiktionary

  • psi|on — «SY on, PSEE », noun. any one of a group of elementary particles related to and including the psi particle: »“Psions”…are thought to possess charm as a hidden property (New York Times). ╂[< psi (particle) + on] …   Useful english dictionary

  • Psi — may refer to:As a word* Psi (Greek) (Ψ, ψ) a letter of the Greek alphabet * Psi (Cyrillic) (Ѱ, ѱ), a letter of the early Cyrillic alphabet, adopted from Greek * Psi (instant messaging client), a popular Jabber client program * Psi… …   Wikipedia


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