Related papers: Spin Determination via Third Generation Cascade De…
The prospects of measuring masses, spin and CP properties within Supersymmetry and other beyond the Standard Model extensions at the LHC are reviewed. Emphasis is put on models with missing transverse energy due to undetected particles, as…
The top quark decays before it hadronises. Before its spin state can be changed in a process of strong interaction, it is directly transferred to the top quark decay products. The top quark spin can be deduced by studying angular…
We study top quark pair production to probe new physics at the LHC. We propose reconstruction methods for $t\bar{t}$ semileptonic events and use them to reconstruct the $t\bar{t}$ invariant mass. The angular distribution of top quarks in…
In the minimal supersymmetric standard model (MSSM) properties of the third generation sfermions are important from the viewpoint of discriminating the SUSY breaking models and in the determination of the Higgs boson mass. If gluinos are…
We study the extent to which spin assignments of new particles produced at the LHC can be deduced in the decay of a scalar or fermion C into a new stable (or quasi-stable) particle A through the chain C \to B^\pm q, B^\pm \to A W^\pm, W^\pm…
Determining the spin of new particles is critical in identifying the true theory among various extensions of the Standard Model at the next generation of colliders. Quantum interference between different helicity amplitudes was shown to be…
Exploiting the azimuthal angle dependence of the density matrices we construct observables that directly measure the spin of a heavy unstable particle. A novelty of the approach is that the analysis of the azimuthal angle dependence in a…
Using an effective field theory approach for higher-spin fields, we derive the interactions of colour singlet and electrically neutral particles with a spin higher than unity, concentrating on the spin-3/2, spin-2, spin-5/2 and spin-3…
Establishing that a signal of new physics is undoubtly supersymmetric requires not only the discovery of the supersymmetric partners but also probing their spins and couplings. We show that the sbottom spin can be probed at the CERN Large…
We propose techniques to observe the correlation of the spins of top quarks and antiquarks at the Tevatron and the LHC. Observation of the spin correlation would confirm that the top quark decays before its spin flips, and would place a…
The spin of supersymmetric particles can be determined at $e^+e^-$ colliders unambiguously. This is demonstrated for a characteristic set of non-colored supersymmetric particles -- smuons, selectrons, and charginos/neutralinos. The analysis…
The recent observation of entanglement between top and anti-top quarks at the LHC opens the way to interpreting collider data with quantum information tools. In this work we investigate the relevance of quantum observables in searches of…
New heavy gauge bosons exist in many models of new physics beyond the standard model of particle physics. Discovery of these W^\prime and Z^\prime resonances and the establishment of their spins, couplings, and other quantum numbers would…
Many models of physics beyond the Standard Model (SM) contain enhanced couplings to third generation particles. The predicted signatures include vector-like quarks and $t\bar{t}$ resonances. We present a review of non-SUSY based searches…
A new particle's interactions can be measured at colliders, by observing its associated production with Standard Model particles. We focus on the case of a collider-stable right-handed top squark and study the LHC sensitivities to its…
Due to its high mass top quarks decay before top-flavoured hadrons can be formed. This feature yields experimental access to the top quark polarization and production asymmetries. The large top quark sample moreover enables measurements of…
Contrary to the general trend of looking for new physics at energies beyond the current reach of the Large Hadron Collider (LHC), this article proposes a strategy to look for light new physics via a meticulous study of well known and…
A number of top-spin observables are computed within the Standard Model (SM), at next-to-leading order in the strong and weak gauge couplings for hadronic top-quark anti-quark (ttbar) production and decay at the LHC for center-of-mass…
If one takes naturalness seriously and also assumes a weakly coupled extension of the Standard Model (SM) then there are predictions for phenomenology that can be inferred in a model independent framework. The first such prediction is that…
The object of this thesis is to study the spin-spin correlations for top quark productions and their decay at polarized e^+e^- linear colliders. For the analyses of the spin-spin correlations in top quark production, we introduce a generic…