J/? particle

The J/ψ is an subatomic particle, namely a flavor-neutral meson consisting of a charm quark and a charm anti-quark. Mesons formed by a bound state of a charm quark and an anti-charm quark are generally known as "charmonium." The J/ψ is the first excited state of charmonium (i.e, the form of the charmonium with the second-smallest rest mass). The J/ψ has a rest mass of 3096.9 MeV/c2 and a half life of 7.2×10-21 s. This lifetime was about a thousand times longer than naively expected.

Related Topics:
Subatomic particle - Flavor - Meson - Charm - Quark - Anti - Bound state - Charmonium - Rest mass - MeV - C - Half life - S

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Its discovery was made independently by two research groups, one at the Stanford Linear Accelerator Center, headed by Burton Richter, and one at the Brookhaven National Laboratory, headed by Samuel Ting. They accidentally discovered they had found the same particle, and both announced their discoveries on November 11, 1974. The importance of this discovery is highlighted by the fact that the subsequent, rapid changes in high-energy physics at the time have become collectively known as the "November Revolution".

Related Topics:
Stanford Linear Accelerator Center - Burton Richter - Brookhaven National Laboratory - Samuel Ting - November 11 - 1974 - High-energy physics

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Richter and Ting were rewarded for their discovery with the 1976 Nobel Prize in Physics.

Related Topics:
1976 - Nobel Prize in Physics

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