Related papers: b-Tagging Algorithms and their Performance at ATLA…
Identification of jets originating from beauty and charm quarks is important for measuring Standard Model processes and for searching for new physics. The performance of algorithms developed to select $b$- and $c$-quark jets is measured…
Recently machine learning algorithms based on deep layered artificial neural networks (DNNs) have been applied to a wide variety of high energy physics problems such as jet tagging or event classification. We explore a simple but effective…
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…
After many years of searches, the Higgs boson was observed by the ATLAS and CMS collaborations in July 2012. Since then, its properties have been measured using primarily the bosonic decay channels: $H \to \gamma\gamma $, $H \to Z Z$, $H…
We study the boosted Higgs tagging using the Lund jet plane. The convolutional neural network is used for the Lund images data set to classify hadronically decaying Higgs from the QCD background. We consider $H\to b \bar{b}$ and $H \to gg$…
A search for strongly produced supersymmetric particles is conducted using signatures involving multiple energetic jets and either two isolated leptons ($e$ or $\mu$) with the same electric charge, or at least three isolated leptons. The…
A calibration of the ATLAS flavour-tagging algorithms using a new calibration procedure based on optimal transportation maps is presented. Simultaneous, continuous corrections to the $b$-jet, $c$-jet, and light-flavour jet classification…
Measurements in the highly Lorentz-boosted regime provoke increased interest in probing the Higgs boson properties and in searching for particles beyond the standard model at the LHC. In the CMS Collaboration, various boosted-object tagging…
We present the results of a detailed study of the effects of $b$-tagging on the heavy top-quark signal and backgrounds for the modes of the di-lepton plus two high transverse energy jets at the Fermilab Tevatron. The general characteristics…
The fragmentation of high-energy gluons at small opening angles is largely unconstrained by present measurements. Gluon splitting to $b$-quark pairs is a unique probe into the properties of gluon fragmentation because identified $b$-tagged…
A search for charged Higgs bosons heavier than the top quark and decaying via $H^\pm \rightarrow tb$ is presented. The data analysed corresponds to 36.1 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}$ = 13 TeV and was recorded with the ATLAS…
We assess the performance of different jet-clustering algorithms, in the presence of different resolution parameters and reconstruction procedures, in resolving fully hadronic final states emerging from the chain decay of the discovered…
This thesis presents a search for a new, hypothetical particle predicted by theories extending the Standard Model of particle physics. This heavy $W'$ boson interacts only with the heaviest known quarks, top and bottom (heavy-philic). Such…
Recent searches for Higgs bosons in the context of extensions to the Standard Model of Particle Physics with the ATLAS detector at the Large Hadron Collider are discussed. All presented analyses use data recorded at a pp center-of-mass…
Due to the high energy and luminosity of the LHC, the ATLAS experiment has a huge discovery potential for new physics. A Standard Model Higgs boson can be discovered over the full range of allowed masses, and its mass should be measured…
Jet taggers provide an ideal testbed for applying explainability techniques to powerful ML tools. For theoretically and experimentally challenging quark-gluon tagging, we first identify the leading latent features that correlate strongly…
We study resonant pair production of heavy particles in fully hadronic final states by means of jet substructure techniques. We propose a new resonance tagging strategy that smoothly interpolates between the highly boosted and fully…
A search for new heavy scalars with flavour-violating decays in final states with multiple leptons and $b$-tagged jets is presented. The results are interpreted in terms of a general two-Higgs-doublet model involving an additional scalar…
The momentum-weighted sum of the charges of tracks associated to a jet provides an experimental handle on the electric charge of fundamental strongly-interacting particles. An overview of a study of this jet charge observable for jets…
A search is performed for narrow resonances decaying to final states of two jets, with at least one jet originating from a b quark, in proton-proton collisions at $\sqrt{s}$ = 13 TeV. The data set corresponds to an integrated luminosity of…