J/psi particle
名词 n.
英 /ˌdʒeɪ ˈsaɪ ˈpɑːtɪkl̩/
美 /ˌdʒeɪ ˈsaɪ ˈpɑɹtɪkəl/|/ˌdʒeɪ ˈpsaɪ ˈpɑɹtɪkəl/
英文释义
名词 n.
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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 report the observation of a heavy particle J, with mass m = 3.1 GeV and width approximately zero.
词源
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.
* 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.
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数据来源: Wiktionary