PART VSUB-ATOMIC PARTICLE PHYSICSY-UpsilonProtons from the high energy accelerator in 1977 at Fermilab were targeted toward a nuclear target. Copper and platinum were used as the targets and detectors were set to find pairs of positive and negative charged muons. Depending upon the initial target utilized, the Y and Y' with opposite signs were found with masses of 9.5 and 10 GeV. The Fermilab proton beam was capable of higher energies than previous experiments and the detector system was compatible for muons rather than lower energy electron-positron detection [1]. This was important in quark theory, because current quark theory was complete, and the "extra particles" necessitated a new kind of quark. It is now accepted that the Y upsilon is related to the psi/J. The new quark is called B and the Y' upsilon is its counterpart with quark spins reversed. [1] Trefil, J. S., 1980. From Atoms to Quarks. New York: C. Scribner & Sons, pp. 182-183. |