eta(c) -> VV problem in constituent quark model

The problem about eta(c) decay into two vector mesons, such as eta(c) --> r ho rho, K*(K) over bar*, phi phi. are discussed in the Bethe-Salpeter frame work. Both constituent quark mass and intrinsic quark transverse motion ins ide the final state mesons are taken into account and their implications ar e discussed The result shows that eta(c) --> VLVT is strictly forbidden Qua rk transverse momentum has apparent effect of enhancing the decay rate. Tho ugh both factors are included, the theoretical value is still smaller than the experimental data.