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Scientists find new subatomic particles

Data appears to have proved the existence of particles made of five quarks, solving a 50-year-old puzzle about the building blocks of matter, researchers said on Tuesday. Quarks are the tiny ingredients of subatomic particles such as protons and neutrons, which are made of three quarks. The less common and more unstable mesons - particles found in cosmic rays - have four. A five-quark version has been sought in 1964 when scientists theorized the existence of such particles.