Discovery of a Second Narrow Resonance ine+e−Annihilation

Possibility of charmoniumlike state X(3915) as χc0(2P)Duan1, Luo2, Liu3 et al. 2020Phys. Rev. D302250View full textAdd to dashboardCite

“…The QPC model is employed to calculate the corresponding partial decay widths (the details of the QPC model can be found in Eqs. (10)-(11)) 3 . We find that taking γ = 0.4, the experimental width of ψ(3770) and ψ(4040) (Γ exp ψ(3770) =27.2 MeV and Γ exp ψ(4040) =80 MeV [47]) can be reproduced here.…”

“…Then, in the subsequent eight years from 1974 to 1982, most of charmonia listed in the present Particle Data Group (PDG) were observed, which becomes the main body of the charmonium family. Here, the typical states include J/ψ [1,2], ψ(3686) [3], ψ(4040) [4], ψ(4415) [5], ψ(3770) [6], ψ(4160) [7], χ c0 (1P) [8], χ c1 (1P) [9], χ c2 (1P) [10], η c (1S ) [11], and η c (2S ) [12]. With these observations, the Cornel model was proposed by Eichten et al [13] in 1975, from which different versions of a potential model [14][15][16][17][18][19] applied to depict the interaction between quarks were developed by different groups.…”

Measurement of the t$\bar{t}$, WW and Z → ττ Production Cross Sections in p$\bar{p}$ collisions at √s = 1.96 TeV

“…Now the Standard Model has six quarks, as listed in The strange quark (s) is a component of so called strange particles, discovered in cosmic rays in the 1950's, whose behavior was resolved with the realization that these particles were produced in pairs of opposite "strangeness". The discovery of the c quark resulted from the observation of very massive meson states in 1974 of type Ψ = cc [22]. The b quark was discovered following the detection of heavier mesons (upsilons) Y = bb in 1977 at Fermilab [23].…”

A Study of B→c$\bar{c}$γK in the BaBar Experiment

“…The understanding of particle physics was revolutionized in 1974 with the discovery of the J/ψ [1] and ψ(2S) [8], identified as cc mesons. These discoveries were the first evidence for the existence of the charm quark, and taken as confirmation of the quark model describing the underlying constituents of baryons and mesons.…”