Lambda particle

From Wikipedia, the free encyclopedia

In particle physics, the Lambda particle is any one of a number of baryons containing an up quark, a down quark, and a third quark such as that the resulting particle exhibits a state of bottomness, strangeness, or is charmed. The first Lambda particle, consisting of an up, down, and strange quark, was discovered in 1947 during a study of cosmic ray interactions. Though the particle was expected to live 10-23 seconds, it actually survived for 10-10 seconds. The property which caused it to live so long was dubbed strangeness, and led to the discovery of the strange quark. Furthermore, these discoveries led to a principle known as the conservation of strangeness, wherein lightweight particles do not decay as quickly if they exhibit strangeness (due to the fact that non-weak methods of particle decay must preserve the strangeness of the decaying baryon).

[edit] References