The associated production of the neutral top-pion with a pair of third family quarks at the hadron colliders

We study the associated production of the neutral top-pion (Pi(O)(t)) with the third famI ily quarks within the context of the topcolor-assisted technicolor model at the hadron colliders. The studies show that, at the Tevatron, the cross-sections of all these processes axe too small to produce enough identified signals. But the cross-sections can be largely enhanced at the LHC. Specially for the processes pp -> tt Pi(o)(t) and pp -> tc Pi(0)(t), the cross-sections can reach the level of a few hundred fb even a few pb for the light neutral top-pion. With the high yearly luminosity 100 fb(-1) at the LHC, over 104 signals can be produced via the above two processes. There exists an ideal flavor-changing mode to detect neutral top-pion, i.e. Pi(0)(t) -> t (c) over bar, because the SM background of such production mode are very clean. Therefore, we can conclude that neutral top-pion should be observable at the LHC via the processes pp -> t (t) over bar Pi(0)(t) and pp -> t (c) over bar Pi(0)(t). On the other hand, the statistics available at the LHC via these two processes might be enough to measure the Yukawa couplings t (t) over bar Pi(0)(t) and t (c) over bar Pi(o)(t). Finally, it must be noted that the study of the process pp -> t (c) over bar Pi(0)(t) can give us a good chance to distinguish the TC2 model from the SM and MSSM because there does not exist such similar tree-level favor-changing process in these models.