Related papers: Supersymmetric Particle Production at HERA
We have performed a search for scalar top quark (stop) pair production in the inclusive electron-muon-missing transverse energy final state, using a sample of $p \bar{p}$ events corresponding to 108.3 pb$^{-1}$ of data collected with the…
We study the pair production of scalar top-quark partners decaying to a top-quark pair plus large missing energy at the LHC, a signature which appears in numerous models that address outstanding problems at the TeV-scale. The severe…
An important tool for interpreting LHC searches for new physics are simplified models. They are characterized by a small number of parameters and thus often rely on a simplified description of particle production and decay dynamics.…
We consider the baryon parity signals at HERA for the case of the MSSM production mechanisms and the decays via the lepton number violating couplings $L_iQ{\bar D}$. We can probe very small Yukawa couplings $\lam' \gsim 3\cdot 10^{-6}$,…
A search for squarks of R-parity violating supersymmetry is performed in $ep$ collisions at HERA using H1 1994 $e^+$ data. Direct single production of squarks of each generation by $e^+$-quark fusion via a Yukawa coupling $\lambda'$ is…
The LHC has strongly constrained models of supersymmetry with traditional missing energy signatures. We present a variety of models that realize the concept of Stealth Supersymmetry, i.e. models with R-parity in which one or more…
Two of the most important parameters in supersymmetry are the masses of the stop and sbottom, the supersymmetric partners of the third generation quarks. A stop mass lighter than 1 TeV is favored theoretically, however, conventional…
Evidence for pair production of a new particle consistent with the Standard Model top quark has been reported recently by groups studying proton anti-proton collisions at 1.8 TeV center of mass energy at the Fermi National Accelerator…
R parity violating trilinear couplings $\lambda'_{1jk}$ of the minimal supersymmetric standard model (MSSM) are constrained from the limit on the electron neutrino mass. Strong limits on these couplings follow from the earlier neglected…
A search, in e^+e^- collisions, for chargino, neutralino, scalar lepton and scalar quark pair-production is performed, without assuming R-parity conservation in decays, in the case that only one of the coupling constants lambda_ijk or…
HERA data on soft hadron production are discussed. The measured inclusive and exclusive hadron cross sections show a simple scaling behaviour.
Searches for supersymmetric partner particles of the top and bottom quarks at the Large Hadron Collider are reviewed. The focus is on the status of searches for a relatively light partner of the top quark performed by the CMS and ATLAS…
A search for anomalous production of events with three or more isolated leptons and bottom-quark jets produced in pp collisions at sqrt(s) = 8 TeV is presented. The analysis is based on a data sample corresponding to an integrated…
The results of a search for pair production of supersymmetric partners of the Standard Model third-generation quarks are reported. This search uses 20.1 fb-1 of pp collisions at sqrt{s}=8 TeV collected by the ATLAS experiment at the Large…
A search for direct production of top squark pairs in events with jets and large transverse momentum imbalance is presented. The data are based on proton-proton collisions at a center-of-mass energy of 13 TeV, collected in 2016 at the CERN…
Supersymmetry, which extends the Standard Model (SM) by introducing supersymmetric partners for the SM particles, can provide an elegant solution to the hierarchy problem. One of the most important parameters in supersymmetry is the mass of…
The cross section of top pair production in hadronic collisions to O(alpha \alpha_s^2) is calculated within the General 2-Higgs-Doublet Model and the Minimal Supersymmetric Standard Model. At the parton level the O(alpha) one-loop…
Supersymmetric models without conservation of R-parity are reviewed and low-energy constraints on the extra trilinear couplings listed. Current searches at the LEP, Tevatron and HERA colliders are then summed up. Prospects for further…
The results of a search for the direct pair production of top squarks, the supersymmetric partner of the top quark, in final states with one isolated electron or muon, several energetic jets, and missing transverse momentum are reported.…
The phenomenology entailed by a scalar resonance in a top partner model is analysed here in a $SO(5)$ Composite Higgs formalism. Heavy scalar resonances production and their decays modes are explored along a benchmark resonance mass range.…