Upsilon particle is a subatomic particle that is about 10 times as massive as a proton. Mass is a measure of the amount of matter in an object. The upsilon particle is unstable and quickly breaks down into lighter particles. It has no electric charge.
Upsilon particles are a type of meson, a particle made up of units called quarks. Upsilon particles consist of a quark and its antimatter counterpart, an antiquark. When such a particle breaks down, the quark and antiquark destroy each other. This destruction results in the release of energy and the creation of lighter particles.
A group of American physicists, led by Leon M. Lederman, discovered the upsilon particle in 1977. They produced the particle by causing high-energy protons to collide with light atomic nuclei. The upsilon particle decays too rapidly to be observed directly. The scientists detected it by observing the lighter particles that resulted from its breakdown. The large mass of the upsilon indicated that its quark was heavier than other quarks that had been discovered. This new quark was named b-quark.
See also Antimatter ; Lederman, Leon Max ; Meson ; Quark .
