Physicists have spied hints of two new members of the family of subatomic particles that includes the proton and neutron. Known as baryons, all such particles contain a trio of more fundamental particles, called quarks.
Although protons and neutrons are made of only so-called down and up quarks, researchers at high-energy particle colliders have for years been detecting exotic baryons containing beefier quarks called strange and charm quarks (SN: 8/25/01,
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