Top-quark pair production via polarized and unpolarized protons in the supersymmetric QCD
Yu Zeng-Hui1,3- Herbert Pietschmann1 - Ma Wen-Gan2,3 - Han Liang3 - Jiang Yi3
1 Institut für Theoretische Physik, Universität Wien,
A-1090 Vienna, Austria
2 CCAST (World Laboratory), P.O. Box 8730, Beijing 100080, P.R. China
3 Department of Modern Physics, University of Science and Technology of China (USTC), Hefei, Anhui 230027, P.R. China
Received: 30 September 1998 / Revised version: 21 January 1999 / Published online: 28 May 1999
The QCD corrections to the top-quark pair production via both polarized and unpolarized gluon fusion in pp collisions are calculated in the minimal supersymmetric model (MSSM). We find that the MSSM QCD corrections can reach 4% and may be observable in future precise experiments. Furthermore, we studied CP violation in the MSSM. Our results show that the CP-violating parameter is sensitive to the masses of SUSY particles (it becomes zero when the c.m. energy is less than twice the masses of both the gluino and the stop quarks) and may reach 10-3.