Observation ine+e−Annihilation of a Narrow State at 1865 MeV/

G. Goldhaber¹,

F. Pierre²,

G. S. Abrams³

et al.

Quarks and leptons beyond the third generation

“…Completion of the second family with the charmed quark, predicted in 1970 [10], was accomplished in 1974 [11][12][13][14]. At first only hidden charm was accessible but two years later explicit charm was detected [15].By this time, a renormalizable gauge theory was available [16-20] based on the first two generations and incorporating the Cabibbo mixing [21] between the two generations.The situation became even more challenging to theorists when experimental discovery of the third generation of quarks and leptons began with the tau lepton, discovered in 1975 [22] in e + e − scattering at SLAC. Next was the bottom quark in 1977 [23,24].…”

“…Completion of the second family with the charmed quark, predicted in 1970 [10], was accomplished in 1974 [11][12][13][14]. At first only hidden charm was accessible but two years later explicit charm was detected [15].…”

A Matter of Kuhnian Theory-Choice? The GWS Model and the Neutral Current

“…The GWS model quickly proved fertile in that it, in Kuhn's words "disclose[d] new phenomena or previously unnoticed relationships among those already known" (Kuhn 1977b, 103). After the discovery of the J/psi-particle in 1974 (Aubert et al 1974c;Augustin et al 1974), which gave ªrst indications of the existence of a new quark, it took another couple of years until physicists had convinced themselves that the GWS model's prediction of the weakly interacting charmed quark was correct (Goldhaber et al 1976). 17 Leading to several further discoveries of new elementary particles-including the IVBs of the weak force in 1983, for which there had been only indirect evidence in the 1970s-the GWS model and its extension to the strong interactions around 1979, culminating in our today's 'Standard Model', turned out to be an extremely fertile research program.…”

A Speculation on the Possible Dynamical Origin of Cabibbo Angle*

“…This paradox was a problem 20 years ago and still remains one, even though the general status of V-A theory has undergone tremendous advancement with the recent progress in gauge theories4 and the discovery of charm particles. 5 The origin of the Cabibbo angle6 may well be the subject that receives the most intensive scrutiny by weak interaction theorists in the coming decade. In this paper, we will limit ourselves with this problem.…”