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We propose that the Y (4260) particle recently announced by BaBar is the first orbital excitation of a diquark-antidiquark state ([cs][cs]). Using parameters recently determined to describe the X(3872) and X(3940) we show that the Y mass is compatible with the orbital excitation picture. A crucial prediction is that Y (4260) should decay predominantly in DsDs. The Y (4260) should also be seen in B non-leptonic decays in association with one kaon. We consider the full nonet of related four-quark states and their predicted properties. Finally, we comment on a possible narrow resonance in the same channel.ROMA1 In a series of exciting experiments, BELLE and BaBar have discovered several states that, although decaying in charmonium plus pions, do not seem to fit the cc picture, in particular the X(3872) and X(3940) states.In a recent paper [1] we have pointed out that the properties of the new states can be well explained if they are S-wave diquark-antidiquark bound states with the composition (q = u, d): [(cq)(cq)] S−wave . An alternative scenario is the molecular picture where the X(3872) would be a D 0 D * 0 bound state. A crucial difference between the two alternatives is that colored objects in a rising confining potential, such as diquarks, should exhibit a series of orbital angular momentum excitations. This is clearly at variance with the molecular picture. Colorless objects bound by a short range potential should have a very limited spectrum, possibly restricted to S-wave states only.In this note we would like to propose that the first orbital excitation of a diquark-antidiquark state may have indeed been found in the state Y (4260) recently announced by the BaBar collaboration [2]. We discuss the properties of the new state in this framework and spell out a few distinctive predictions. The most revealing among them is that the dominant decay mode of Y (4260) should be in D sDs pairs. We shall also briefly discuss other states implied by the scheme and their properties. We comment on the possibility of an additional narrow state.The Y (4260) is observed by BaBar in e + e − annihilation, in association with an Initial-State-Radiation pho- * Electronic address: luciano.maiani@roma1.infn.it † Electronic address: veronica.riquer@cern.ch ‡ Electronic address: fulvio.piccinini@pv.infn.it § Electronic address: antonio.polosa@cern.ch ton, which implies J P C = 1 −− . The particle has a width of about 90 MeV and it is seen to decay in J/ψ π + π − . The π + π − mass distribution peaks around 1 GeV, consistently with a decay into J/ψ f 0 (980). BaBar reports the value [2]:(1) The diquark-antidiquark assumption together with the negative parity call for at least one unit of orbital angular momentum. In addition, the decay into f 0 (980), which fits the (

Heavy-light diquarks can be the building blocks of a rich spectrum of states which can accommodate some of the newly observed charmonium-like resonances not fitting a pure cc assignment. We examine this possibility for hidden and open charm diquark-antidiquark states deducing spectra from constituent quark masses and spin-spin interactions. Taking the X(3872) as input we predict the existence of a 2 ++ state that can be associated to the X(3940) observed by Belle and re-examine the state claimed by SELEX, X(2632). The possible assignment of the previously discovered states Ds(2317) and Ds (2457) is discussed. We predict X(3872) to be made of two components with a mass difference related to mu − m d and discuss the production of X(3872) and of its charged partner X ± in the weak decays of B +,0 .

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