Dictionary

J/psi particle en · NOUN

Pronunciation

• /ˌdʒeɪ ˈsaɪ ˈpɑːtɪkl̩/ (UK)
• /ˌdʒeɪ ˈsaɪ ˈpɑɹtɪkəl/ (US)
• /ˌdʒeɪ ˈpsaɪ ˈpɑɹtɪkəl/ (US)

Etymology

A compound of J, ψ (ps) (psi), and particle. The particle was discovered independently in 1974 by two research groups, leading to the "November Revolution" in particle physics. * The group led by Samuel Ting at Brookhaven National Laboratory proposed the name J, reputedly because the shape of the Chinese character for Ting (丁) resembles a J, though Ting also cited the symbol for electromagnetic current, j_μ(x), as a reason. * The group led by Burton Richter at SLAC proposed the name ψ (psi). Richter initially preferred "SP" (for the SPEAR accelerator), but chose "psi" as it contained "SP" in reverse order and was the only remaining Greek letter deemed suitable; coincidently, the particle's decay pattern in spark chambers resembled the letter ψ. The compromise name J/ψ was adopted to acknowledge both discoveries.

Meanings

1. (particle) A subatomic particle with an unusually long lifetime (7.2 × 10⁻²¹ s) and a large mass (approx. 3.097 GeV/c²); a bound state of a charm quark and an anti-charm quark (the most common form of charmonium).
   • We denote this resonance as ψ(3105). 1974, J. E. Augustin et al., “Discovery of a Narrow Resonance in e⁺e⁻ Annihilation”, in Physical Review Letters, volume 33, number 23, →DOI, pages 1406–1408:
   • We report the observation of a heavy particle J, with mass m = 3.1 GeV and width approximately zero. 1974, J. J. Aubert et al., “Experimental Observation of a Heavy Particle J”, in Physical Review Letters, volume 33, number 23, →DOI, pages 1404–1406:

Forms

Hypernyms

hadron · quarkonium · charmonium · meson · boson · vector meson

Synonyms

J/psi meson · psion

Translations (10)

cmn ψ介子 (subatomic particle) · ja ジェイプサイ中間子 (subatomic particle) · ru J (subatomic particle) · ru ψ-мезон (subatomic particle) · cmn J (subatomic particle) · fr méson J/ψ (subatomic particle) · de J (subatomic particle) · es mesón J/ψ (subatomic particle) · de ψ-Meson (subatomic particle) · it mesone J/ψ (subatomic particle)

wikipedia: Burton Richter · wikipedia: Samuel Ting · wikipedia: SLAC · wikipedia: Brookhaven National Laboratory · wikipedia: SPEAR