Study of the single neutral toppion production process at gammagamma collider.pdfVIP

Study of the single neutral top-pion production process at γγ collider Xuelei Wanga,b , Xiaoxue Wangb,c 5 a: CCAST(World Laboratory) P.O. BOX 8730. B.J. 100080, P.R.China 0 0 2 b: College of Physics and Information Engineering, v o Henan Normal University, Xinxiang 453007, P.R.China N 8 c: College of Physics and Chemistry, 1 2 Henan Polytechnic University, Jiaozuo, Henan, 454000, P.R.China ∗† v 5 February 2, 2008 9 3 0 1 5 0 Abstract / h 0 p γγ → Πt is the major production mechanism of neutral top-pion at the linear - p colliders. In this paper, we calculate the cross section of the process γγ → Π0 and t e h discuss the potential to observe the neutral top-pion via its various decay modes at : v i the planned ILC. The study show that, among the various neutral top-pion production X 0 r processes at the linear colliders, the cross section of γγ → Πt is the largest one which a can reach the level of 101 − 102 fb. Due to the existence of the tree-level flavor-changing coupling Π0tc¯, γγ → Π0 → tc¯ can provide enough number of typical signals to identify t t the neutral top-pion with the clean SM background. Therefore, the process γγ → Π0