Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı

Ckm-Suppressed Top Quark Decays in Standard Model (Sm) and Beyond at Ilc

After the discovery of the top quark at Fermilab Tevatron Collider, experimental attention has been on the creation of quark and decay mechanisms. While the top quark production cross section in Standard Model (SM), has been evaluated as 15% uncertainty, it is assumed that a b quark and a W boson decaying in the 100% of the time. Because of its extremely heavy mass, it is expected that top quark will have a relationship with new physics. It is also thought that it will provide some clues about the nature of top quark’s electroweak symmetry breaking mechanisms. In this way, it can serve as a window to measure top quark’s properties SM and beyond physics. As a lot of experimental data shows, the interaction between quarks and leptons gauge bosons was defined correctly by SU(3)c × SU(2)_L × U(1)_Y.

Top quark decays, for both dominant (t → b +W) and rare (t → q +W, cV, cVV, c, BW Z) decay types has a special attention as a tool to test the Standard Model predictions. Since rare decays has fairly suppressed, they are perfect windows in order to analyze SM and beyond predictions. Especially from new physics, corrections to t → q + W (q = d, s) CKM-suppressed SM top quark decay and both among the effective models using right-hand currents and Minimal Supersymmetric Standard Model (MSSM) are evaluated. At the same time, new point of views are handled in order to research the predictions at ILC (International Linear Collider).