Séminaire de Doctorant 2eme année: Search for new resonances in ttbar final states with the ATLAS detector using Run 2 data.

par M. Silvestre Marino ROMANO-SAEZ (LPC-Clermont)

vendredi 13 nov. 2015, 14:30 → 15:30 Europe/Paris

Salle 9110 (Dept.Phys.)

Beyond-the-Standard-Model (BSM) theories are developed to provide answers to the limitations of the SM and probing BSM theories is one of the goals of the LHC physics program. The search for ttbar resonances performed by the ATLAS collaboration is part of this program and will be presented in the seminar. Due to its high mass, the top quark could be strongly coupled to BSM particles. Therefore, heavy BSM particles can be expected to decay in pair of top quarks, where the evidence of new resonances should appears as a peak or a dip in the ttbar mass spectra. The first part of the presentation will summarize the instrumentation work performed for the TileCal calibration, a crucial element in top-quark physics. The second part is dedicated on the perspectives for the search of the particles predicted by two Higgs doublet model (2HDM), which are phenomenologically appealed to decay in pair of top quarks. The signal of the new resonances interferes with the SM processes, showing a peak/dip structure. The third part of the presentation covers the current status on the search of new ttbar resonances with the first Run 2 datasets, where the leptophobic Top Color heavy Z' is the benchmark model used.