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Xi particle

In particle physics, Ξ (Xi) is a name given to a range of baryons with one up or down quark and two heavier quarks. They are sometimes called the cascade particles because of their unstable state, they decay rapidly into lighter particles through a chain of decays. The first discovery of the Xi particle was at Brookhaven National Laboratory in 1964.[1]

Xi particle
Particle Symbol Makeup Rest mass
S C B Mean lifetime
Main decay
Xi Ξ0 uss 1315 -2 0 0 2.9×10-10 Λ0 + π0
Xi Ξ- dss 1321 -2 0 0 1.6×10-10 Λ0 + π-
charmed Xi Ξ+c usc 2466 -1 +1 0 4.4×10-13
charmed Xi Ξ0c dsc 2472 -1 +1 0 1.1×10-13
bottom Xi Ξ0b usb -1 0 -1
bottom Xi Ξ-b[2][3][4][5] dsb 5792±3 -1 0 -1 1.4×10-12 J/Ψ + Ξ- (seen)

The Ξ-b particle is also known as the cascade B particle and contains quarks from all three families.


  1. ^
  2. ^
  3. ^ Fermilab physicists discover "triple-scoop" baryon. Fermilab (2007-06-13). Retrieved on 2007-06-14.
  4. ^ Back-to-Back b Baryons in Batavia. Fermilab (2007-06-25). Retrieved on 2007-06-25.
  5. ^ "Observation and mass measurement of the baryon Xi(b)-"
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Xi_particle". A list of authors is available in Wikipedia.
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