You need a little luck and huge accelerator - a ring of several kilometres diameter, consuming electricity like a medium-size city.
1, 2. The first pair – “up” and “down” are everywhere, being components of atomic nuclei.
|
|
![]() 3. The lighter of the second pair, “strange” is a consituent of particles heavier than proton and neutron and observed in cosmic radiation in 40-ies. These strange particles can be captured atomic nuclei for a glimpse, before decaying. This picture shows a first noticed trace in the photographic emulsion of a decaying hypenucleus. M. Danysz and J. Pniewski, J. Phil. Mag. 44 (1953), 348 |
|
![]() J.-E. Augustin et al., Phys. Rev. Lett. 33, 1406–1408 (1974)
|
4. The “charm”, completing the second generation was subject to double hunting: in Brookhaven a narrow peak was observed at 3.1 GeV for electron- positron pairs production in
p+Be collisions, in Stanford vice-versa – a peak for hadron production in electron- positron annihilation; the papers were submitted with one day difference, the cc meson brings a double name
J/Ψ and the Noble prize was shared by both groups
|
Discovery of the Charmed Baryon |
![]()
|
![]() ![]()
|
5. The third generation was first predicted theoretically by M. Kobayashi and T. Masakawa in 1974. The “bottom” quark called also “beauty” was observed in 1977 in FermiLab in production of muons from proton scattering on Cu or Pt, as a faint “bump” (Y - Upsilon meson bb ) at 9.5 GeV mass.
|
6. The last, “top” is so heavy (175 GeV) that becomes a father for generations of other particles – so called jets; its mass was predicted correctly by the theory and was measured with the best accuracy in the whole quark zoo. |
|
![]() ![]() A computer simulation of a proton-antiproton collision.
|
![]() ![]()
|
![]()
Bigger and bigger machines are needed to find small quarks. |
|
Special credits to FermiLab for permission to use internet material |