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The DZero experiment at Fermilab recently discovered the Cascade-b particle, which contains a down quark (d), strange quark (s) and bottom quark (b). It is the first particle ever observed with one quark from each generation of particles. The Cascade-b particle (\u039eb) is short-lived. Once produced, it travels only several millimeters before the action of the weak nuclear force causes it to disintegrate into two well-known particles called J/\u03a8 and \u039e-. The J/\u03a8 then promptly decays into a pair of muons, common particles that are cousins of electrons. The \u039e- baryon, on the other hand, travels several centimeters before decaying into yet another unstable particle called a \u039b baryon, along with another long-lived particle called a pion. The \u039b baryon too can travel several centimeters before ultimately decaying to a proton and a pion.
Image and text courtesy the DZero Collaboration at Fermilab.