Related papers: Reconstructing the Chargino System at $e^+e^-$ Lin…
Supersymmetric models are typically taken to have $\mu$ parameter and all soft supersymmetry breaking parameters at or near the weak scale. We point out that a small window of allowed values exists in which $\mu$ and the electroweak gaugino…
The data recorded by the ALEPH detector at centre-of-mass energies of 161, 170, and 172 GeV are analysed for signals of chargino and neutralino production. No evidence of a signal is found, although candidate events consistent with the…
This thesis presents a theoretical analysis of the properties of the Higgs bosons in the Standard Model (SM) and the minimal supersymmetric extension (MSSM), which can be investigated at the LHC and $e^+e^-$ linear colliders. The final goal…
In this letter, we study collider phenomenology in the supersymmetric Standard Model with a certain type of non-universal gaugino masses at the gauge coupling unification scale, motivated by the little hierarchy problem. In this scenario,…
The supersymmetric extension of the standard model with an additional gauge singlet is analysed in detail in the light of the recent experimental bounds on supersymmetric particles. The useful part of the parameter space and the particle…
The simplest interpretation of the global success of the Standard Model is that new physics decouples well above the electroweak scale. Supersymmetric extension of the Standard Model offers the possibility of light chargino and the…
A search for a chargino$-$neutralino pair decaying via the 125 GeV Higgs boson into photons is presented. The study is based on the data collected between 2015 and 2018 with the ATLAS detector at the LHC, corresponding to an integrated…
A search was performed for charginos with masses close to the mass of the lightest neutralino in e+e- collisions at centre-of-mass energies of 189-209 GeV recorded by the OPAL detector at LEP. Events were selected if they had an observed…
The potential of muon colliders to study a low-energy supersymmetry is addressed in the framework of the minimal supergravity model, whose predictions are first briefly surveyed. Foremost among the unique features of a muon collider is…
If supersymmetry (SUSY) is realized at the electroweak scale, its underlying structure and breaking mechanism may be explored with great precision by a future linear $e^+ e^-$ collider (LC) with a clean environment, tunable collision…
Associated selectron-neutralino production in the process $e^-\gamma\to\tilde e^-\tilde\chi^0$ provides a striking supersymmetric signal: events with a single high $p_\perp$ electron and otherwise only invisible particles. For $e^-\gamma$…
We show that the interplay between the LHC and the e^+ e^- International Linear Collider (ILC) with sqrt{s}=500 GeV might be crucial for the discrimination between the minimal and next-to-minimal supersymmetric standard model. We present an…
Several extended supersymmetric models, motivated by either grand unification, or by neutrino mass generation, predict light doubly charged higgsinos. We study the production of a single doubly charged higgsino and its decay channels at the…
We study LHC phenomenology of mirage mediation scenario in which anomaly and modulus contributions to soft SUSY breaking terms are comparable to each other. A Monte Carlo study of mirage mediation, with model parameters $\alpha=1$,$…
The requirement that the lightest neutralino $\tilde\chi_1^0$ has the right thermal relic density to explain all Dark Matter in the universe strongly constrains the parameter space of supersymmetric models in general, and of the mSUGRA…
We study a simplified scenario in the next-to-minimal supersymmetric standard model with a split electroweak spectrum, in which only the singlino and higgsinos are light and other superpartners are decoupled. Serving as a dark matter…
We correct our treatment of decays of the lightest chargino to final states containing the lightest neutralino in the case where the chargino and neutralino masses differ by less than 1 GeV. A brief summary of the phenomenological…
With the process $e^-\gamma \to \tilde{\chi}_1^0 \tilde{e}_{L/R}^- \to e^- \tilde{\chi}_1^0 \tilde{\chi}_1^0$ it is possible to constrain selectron masses above the kinematical limit of the pair production process in $e^+e^-$ colliders. We…
The requirement of electroweak naturalness in simple supersymmetric models implies the existence of a cluster of four light higgsinos with mass $\sim 100-300$\,GeV, the lighter the better. While such light compressed spectra may be…
The physics potential of discovering and exploring supersymmetry at future e^+e^- linear colliders is reviewed. Such colliders are planned to start to operate at a center-of-mass energy of 500 GeV to 800 GeV, with a final energy of about 2…