Study of B(B)over-bar*/D(D)over-bar* bound states in a Bethe-Salpeter approach

In this work the B (B) over bar*/D (D) over bar* system is studied in the Bethe-Salpeter approach with quasipotential approximation. In our calculation both direct and cross diagrams are included in the one-boson-exchange potential. The numerical results indicate the existence of an isoscalar bound state D (D) over bar* with J(PC) = 1(++) which may be related to the X(3872). In the isovector sector, no bound state is produced from the interactions of D (D) over bar* and B (B) over bar*, which suggests the molecular state explanations for Z(b)(10610) and Z(c)(3900) are excluded.