Search for a Fermionic Top Partner Using 13 TeV Data at the LHC
This event is part of the Departmental Seminars.
Dissertation Committee: Tulika Bose, Kevin Black, Shyam Erramilli, Kenneth Lane, James Rohlf
Following a two year shutdown, in 2015 the LHC restarted and successfully began proton-proton collisions at a record center-of-mass energy of 13 TeV. With the discovery in Run 1 of the Higgs boson, one of the most pressing questions we hope the new data can answer is the so called ‘Hierarchy Problem’. Several extensions of the Standard Model predict new, heavy particles in order to stabilize the Higgs mass, examples of which include new, heavy fermions from Composite Higgs theories. My talk will focus on the search for a fermionic partner of the top quark with an exotic charge of 5/3 that of the electron (referred to as X53). The search presented is for a final state with same-sign dileptons , which is a very clean and rare channel with respect to Standard Model Processes. Results are presented using the CMS dataset corresponding to roughly 2.2 /fb. No significant excess of events compared to the predicted background is observed and the mass of the X53 is excluded to be below 950 (910) GeV for a right (left) handed X53 particles.