Related papers: Data-driven Estimations of Z, W and Top Background…
Top quark physics measurements performed using data from the ATLAS detector at the LHC rely on efficient reconstruction and precise calibration of leptons, jets and missing transverse energy. A review of the techniques used to reconstruct…
This dissertation focuses on phenomenological studies for possible signals for supersymmetric events at the Large Hadron Collider (LHC). We have divided our endeavours into three separate projects. First, we consider SUSY models where the…
The discovery potentials of ATLAS and CMS experiments at the Large Hadron Collider (LHC) for Supersimmetry (SUSY), Extra Dimensions (ED), new Gauge Bosons and R-Hadrons are discussed. Beyond Standard-Model (BSM) searches at LHC require a…
This work presents a new inclusive search for supersymmetry (SUSY) by the ATLAS experiment at the LHC in proton-proton collisions at a center-of-mass energy sqrt(s) = 7 TeV in final states with jets, missing transverse momentum and one or…
A search is presented for new phenomena in events characterised by high jet multiplicity, no leptons (electrons or muons), and four or more jets originating from the fragmentation of $b$-quarks ($b$-jets). The search uses 139 fb$^{-1}$ of…
The identification of top quark decays where the top quark has a large momentum transverse to the beam axis, known as $top$ $tagging$, is a crucial component in many measurements of Standard Model processes and searches for beyond the…
Alternative top quark mass determinations can provide inputs to the world average with orthogonal systematic uncertainties and may help to refine the interpretation of the standard method. Among a number of recent results I focus on the…
Measurements are presented of the jet invariant mass and substructure in proton-proton collisions at sqrt{s} = 7 TeV with the ATLAS detector using an integrated luminosity of 37 pb-1. These results exercise the tools for distinguishing the…
Over the past decade, a large number of jet substructure observables have been proposed in the literature, and explored at the LHC experiments. Such observables attempt to utilize the internal structure of jets in order to distinguish those…
An overview of the most recent results on top quark physics obtained using proton-proton collision data collected with the ATLAS and the CMS experiments at 7 TeV center-of-mass energy is given. Measurements for inclusive and differential…
We present the status of interpretations of Supersymmetry (SUSY) searches in ATLAS at the Large Hadron Collider (LHC) using simplified models. Such models allow a systematic scan through the phase space in the sparticle mass plane, and in…
The leptonic decays of the heavy gauge bosons W and/or Z provide a clear experimental signature at hadron colliders. The production of accompanying jets is an excellent signal to probe QCD, while also being the main background to many…
We study the reconstruction of high p_T hadronically-decaying top quarks at the LHC. The main challenge in identifying energetic top quarks is that the decay products become increasingly collimated. This reduces the efficacy of conventional…
A search for production of supersymmetric particles in final states containing jets, missing transverse momentum, and at least one hadronically decaying tau lepton is presented. The data were recorded by the ATLAS experiment in sqrt(s) = 7…
The ATLAS potential for the study of the top quark properties and physics beyond the Standard Model in the top quark sector, is described. The measurements of the top quark charge, the spin and spin correlations, the Standard Model decay…
Top plus jets production at hadron collider allows us to study the couplings of the top quark. In the Standard Model, two single top processes contribute to the top-jets final state. Beyond the Standard Model, additional direct top…
Theoretical predictions of top-quark cross sections depend on the values of the parameters of the quantum chromodynamics Lagrangian, such as the strong coupling constant and the mass of the top quark, but also on parameters of the…
This paper discusses the ATLAS potential to study Supersymmetry for the "Focus-Point" region of the parameter space of mSUGRA models. The potential to discovery a deviation from Standard Model expectations with the first few ${fb}^{-1}$ of…
This report summarizes recent results of differential top quark cross section measurements performed by the ATLAS and CMS experiments. The $t\bar{t}$ process is studied as well as the production of single (anti-)top quarks and the…
The production of a top quark in association with a $Z$ boson is investigated. The proton--proton collision data collected by the ATLAS experiment at the LHC in 2015 and 2016 at a centre-of-mass energy of $\sqrt{s} = 13 \mathrm{TeV}$ are…