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11 February 1998
The "omega-minus" - the last piece in a puzzle
On 11
February 1964, a team from the Brookhaven
National Laboratory, Long Island, New York, sent an historic
paper to the journal Physical Review
Letters*,
announcing the discovery of the particle dubbed the
"omega-minus". It was the last piece in a subatomic
puzzle put together independently by theorists Murray Gell-Mann and Yuval Ne'eman. Their puzzle
related different particles through their properties of electric
charge and "strangeness", but one particle, with
negative charge and three units of strangeness was missing. This
was the particle Gell-Mann called the omega-minus, and this
week's image shows that historic first observation, recorded in Brookhaven's
80-inch hydrogen
bubble chamber. The trail of the omega-minus,
about 2-cm long, can be seen as the short track just below the
track that abruptly heads off to the right, in the lower half of
the image (see here for a detailed diagram). This discovery
confirmed the importance of the relationships between many particles, which
was soon to be understood in terms of their underlying structure
in the form of quarks.
(* See Physical Review Letters 12 204 (1964))
Credit: Brookhaven National Laboratory
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