Tetraquark state candidates: Y (4140), Y (4274) and X (4350)

In this paper, we tentatively assign the Y (4140), Y (4274) and X(4350) to be the scalar and tensor cs (c) over bar(s) over bar tetraquark states, respectively, and study them with the QCD sum rules. In the operator product expansion, we take into account the vacuum condensates up to dimension-10. In calculations, we use the formula mu = root M-X/Y/Z(2) - (2M(c))(2) to determine the energy scales of the QCD spectral densities. The numerical results favor assigning the Y (4140) to be the J(PC) = 2(++) diquark-antidiquark type tetraquark state, and disfavor assigning the Y (4274) and X (4350) to be the 0(++) or 2(++) tetraquark states.