Scientists working at the Collision Detector at Fermilab (CDF) experiment have confirmed the observation of a new particle, the Xi-sub-b. The new particle is categorized as a baryon, which are formed of three quarks -- a commonly known baryon is the proton. Scientists have predicted the existence of the Xi-sub-b, but have never observed it until now, describing it as "a heavy relative of the neutron and is six times heavier than the proton or neutron." The Xi-sub-b was produced in Batavia, Illinois at the Tevatron particle accelerator and collider, which incorporates the CDF experiment.
According to the scientists, the "neutral Xi-sub-b travels just a fraction of a millimeter before it decays into lighter particles," which probably explains why scientists predicted its existence, but weren't able to observe it until now. Emphasizing how rare it is to actually observe the Xi-sub-b particle, only 25 instances of it were observed out of 500 trillion proton-antiproton collisions.
(ConceivablyTech via Wired UK)