J/psi particle

短语

ψ介子

发音

UK /ˌdʒeɪ ˈsaɪ ˈpɑːtɪkl̩/
US /ˌdʒeɪ ˈsaɪ ˈpɑɹtɪkəl/
US /ˌdʒeɪ ˈpsaɪ ˈpɑɹtɪkəl/

词形变化

J/psi particles J/ψ particle J/psi particles 复数 J 复数 psi particles 复数

别名

J/ψ meson J/psi meson J/ψ particle J particle psion

释义与例句

n.
  1. 1.

    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).

    ψ介子

    物理

词源

A compound of J, ψ (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.

来源：wiktionary