Search for Heavy 5/3 Charge Fermionic Top Quark Partner in Same-Sign Dilepton Final State using 13 TeV Data with the CMS Detector

Speaker: David Zou

When: October 10, 2019 (Thu), 02:15PM to 03:45PM (add to my calendar)
Location: PRB 595

This event is part of the PhD Final Oral Exams.

Examining Committee: James Rohlf, Indara Suarez, Kenneth Lane, Claudio Chamon, John Butler


The discovery of the Higgs boson in 2012 was an important and exciting moment in the world of high energy particle physics. But unanswered questions, including the Higgs mass fine tuning problem remain, motivating current and future physics searches beyond the Standard Model. Composite Higgs theories predict new, heavy fermions which stabilize the Higgs mass. One such particle, the X53, is a fermionic top quark partner with an exotic 5/3 electric charge and can be produced via pair or single production. The X53 search in the same-sign dilepton final state is presented, showing results of the search for pair and single produced X53 using the data from proton-proton collisions at a center-of-mass energy of 13 TeV collected by the Compact Muon Solenoid (CMS) experiment between 2015 and 2016. No significant excess of events with respect to the predicted Standard Model backgrounds is observed, and limits are placed on the mass at 95\% confidence level. The mass of the X53 is excluded below 1200 (1160) GeV for a X53 with right (left) handed couplings to the W boson.