Study of top quark pair production near threshold at the ILC

Abstract

We report on a study of top pair production at the International Linear Collider (ILC) around center of mass energy (E${}_{\mathrm{CM}}$) = 350 GeV using an ILD detector simulator based on the Detailed Baseline Design (DBD) configuration. Here we will report on a result of 6-Jet final state, $tbart\to bWbW\to bqqbqq$. A result for the 4-Jet final state, $tbart\to bWbW\to bqqbl\nu$, which has almost the same statics as that of the 6-Jet final state will be included in the future. For an energy scan of 11 center of mass energy points (340 - 350GeV) and two beam polarization combinations (P($e^{+},e^{-}$) = ($\pm$0.3, $\mp$0.8)) with 10 fb${}^{-1}$ each, the statistical errors on the top quark Yukawa coupling, its mass and width are estimated. The results are $\delta y_t$ = 4.2%, $\delta m_t$ = 16 MeV in potential subtracted scheme (PS), and $\delta {\Gamma }_t$ = 21 MeV.

Comments: 14 pages, 11 figures, 4 tables