Study of a flavor-changing neutral top-pion production processe+e−→tc¯Πt0

Abstract

We study a flavor-changing top-pion production process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}t\overline{c}{\ensuremath{\Pi}}_{t}^{0}$ in the top-color-assisted technicolor (TC2) model. The studies show that, with the high center of mass energy in the DESY TESLA collider, the production cross section of ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}t\overline{c}{\ensuremath{\Pi}}_{t}^{0}$ is at the order of magnitude 0.1 fb in most parameter regions of the TC2 model and a few tens of events of a top-pion production can be produced each year. The resonance effect can enhance the cross section to a few fb when the top-pion mass is small. With a clean background, the top-pion events can possibly be detected at the TESLA collider. On the other hand, we find that there exists a narrow peak near ${m}_{t}\ensuremath{-}{m}_{c}$ in the top-pion--charm invariant mass distribution which could be clearly detected. Therefore, such a top-pion production process ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}t\overline{c}{\ensuremath{\Pi}}_{t}^{0}$ provides a unique chance to detect top-pion events and test the TC2 model.