Anti-B meson

In such B-factories, the separation of pions from kaons is vital for the identification of B- or anti-B-meson and the selection of rare decays. It is important to measure the decay time from the appearance of B-mesons to the final state. 

Figure 28.15. Violation of CP symmetry measured by BELLE in 2006 difference of the decay time distribution between B-mesons and anti-B-mesons.

A Stanford Linear Accelerator Center (SLACO PEP-II collider). Electrons (blue) and positrons (pink) circulate in opposite directions along the two rings before being forced to collide. These collisions produce large quantities of subatomic particles (e.g., "B mesons and anti-B mesons"). 

B-meson Symbol B . A meson that consists of a down quark and an anti-bottom quark. 

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