Charmed baryons

Charmed baryons are a category of composite particles comprising all charm quark. These particles were first observed in the 1970s; since then, a large number of distinct charmed bayron states have been identified. In 2002, the SELEX collaboration published evidence of a doubly charmed baryon, but this claim has yet to be confirmed by another experiment.

History

The first charmed baryon to be discovered was the Λ⁺_c. It is not entirely clear when the particle was first observed; there were a number of experiments which published evidence for the state beginning in 1975, but the reported masses were frequently lower than the real value. Since then, Λ⁺_c have been produced and studied at many experiments, notably fixed-target experiments (such as FOCUS and SELEX) and e⁺e^- B-factories (ARGUS, CLEO, BABAR, BELLE).