New look at scalar mesons.
Light scalar mesons are found to fit rather well a diquark-antidiquark description. The resulting nonet obeys mass formulas which respect, to a good extent, the Okubo-Zweig-Iizuka (OZI) rule. OZI allowed strong decays are reasonably reproduced by a single amplitude describing the switch of a qq pair, which transforms the state into two colorless pseudoscalar mesons. Predicted heavy states with one or more quarks replaced by charm or beauty are briefly described; they should give rise to narrow states with exotic quantum numbers.
Maiani
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Università di Roma La Sapienza, INFN, Rome, Italy. luciano.maiani@roma1.infn.it
Piccinini
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Polosa
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AD
Riquer
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