Résumé du preprint Irfu-15-31

Irfu-15-31
Top Quark Precision Measurements with the D0 Detector (Habilitation à diriger des recherches - HDR)
V. Sharyy
For 24 years the Tevatron proton-antiproton collider was the collider with the highest collision energy in the world. It was in operation from 1988 to 1996 with a center-of-mass energy of 1.8 TeV (Run I) and after numerous upgrades from 2002 to September 2011 with a center-of-mass energy of 1.98 TeV (Run II). Two collaborations, D0 and CDF, exploited the Tevatron facility and realized a waste physics program. The principal directions of this program are the Higgs boson search, search for the non-standard phenomena, precise measurement of W boson mass, heavy flavor physics, QCD and top quark physics. One of the main Tevatron achievement is a discovery in 1995 the heaviest elementary particle, the top quark. From 1995 and up to now, both, D0 and CDF collaborations, have studied the top quark in great details. This HDR manuscript describes my 11 years research activity in the D0 experiment. In the beginning of the Run II data taking period, my main contribution was the operation of the D0 calorimeter, development of the calorimeter on-line monitoring software, an extensive study of the external and internal sources of noise and development of the system of the data quality monitoring and selection. My another important contribution to the D0 experiment was the work on the off-line treatment of data events prior to the physics analysis. In particular, I contributed to the development of the common analysis environment, used to select and process events in the standard and certified way by most of the physics analysis at the D0. In addition, I participated in the design, planning and coordination of this activity as a convener of the common samples physics group in 2007-2009 and V+jets group in 2009-2010. The activity related to the detector operation and to the development of the common analysis environment is described in the chapter 1 of the manuscript. In 2004 I started studies of the top quark, mainly in the dilepton final state. In particular, I worked on the selection and separation of top quark-antiquark (ttbar) events from the background events, the ttbar production cross-section measurement, search for non SM decays of the top quark, e.g. search for a charged higgs boson, measurement of the ratio of the branching fractions. With increase in the integrated luminosity, the precise measurement of the top quark properties became possible: the measurement of the top quark mass, asymmetry in the angular distributions of the top quark. In addition, I participated in the coordination of the top quark group activity, development of the analyses strategy, presentations and publications of results, combinations of the Tevatron measurements, as a dilepton subgroup convener in 2007-2009 and as a top group convener from 2011 and up to now. These studies and results of the measurements are presented in the chapter 2 of the manuscript.