Related papers: Supersymmetric interpretation of high--$Q^2$ HERA …
We investigate an event excess in the reaction $e^+p \to e^+ X$ with large $x$ and high $Q^2$ observed at HERA and show that the events could naturally be interpreted as a signature of the production of the scalar top quarks (stops) in a…
We examine the possibility that the high-Q^2 events seen at HERA are due to the production and decay of squarks of R-parity violating supersymmetry. The relevant R-parity violating coupling(s) is identified and shown to lie between 0.03 and…
We investigate a production process $e^+p \to \st X \to \sb W^+ X$ at HERA, where we consider a decay mode $\sb \to \bar{\nu}_e d$ of the sbottom in the framework of an R-parity breaking supersymmetric standard model. Both processes of the…
We summarise possible explanations of the HERA large-Q^2 data, in the framework of R-parity violating supersymmetry. Experimental limits indicate that the most likely production channels are e^+ d --> scharm_L, e^+ d --> stop and e^+ s -->…
We summarize two sets of signals at HERA in supersymmetric models with explicitly broken R-parity. (1) The resonant production of single squarks through an operator $L_1Q_i{ \bar D}_j$. (2) The MSSM production of a squark and a slepton…
This talk is divided in two parts. In the first one we discuss the signals of the Minimal Supersymmetric Standard Model through the production of \tilde{e} \tilde{q}. The second part is devoted to contact terms. The bounds on the mass scale…
The excess of high $Q^2$ events at HERA reported in the early 1997 by H1 and ZEUS collaborations has become the subject of extensive studies in the framework of several models related to new physics. Here we concentrate on the most…
A search for stop production in R-parity-violating supersymmetry has been performed in $e^{+}p$ interactions with the ZEUS detector at HERA, using an integrated luminosity of 65 pb$^{-1}$. At HERA, the R-parity-violating coupling $\lambda'$…
Events with an isolated high $p_T$ lepton, a hadron jet and missing energy as observed in the H1 experiment at HERA, are potentially associated with R-parity violation in supersymmetric theories. However, stringent kinematic constraints…
We investigate the $e^+p \to \mu^+ X$ event with high transverse momenta observed at HERA (H1) and show that this event could be interpreted as a signature of the single production of the scalar top quark in a supersymmetric model with…
In the framework of the minimal supersymmetric standard model and the $R$-parity breaking model, we investigate various production processes of the supersymmetric partner at HERA energies. Our emphasis is paid upon the scalar top quark, the…
The excess in high-Q^2 events at HERA is introduced and possible explanations within the framework of R-parity violating supersymmetry are discussed.
We examine the stop production scenario for the anomalous excess of high $Q^2$ events observed at HERA, by taking into account the constraints coming from the leptoquark search at Tevatron and the atomic parity violation experiments. This…
We discuss the recently observed excess of high Q2 neutral current deep inelastic scattering events at HERA in the light of supersymmetry with broken R-parity. We find more than one possible solution. We consider the possibilities for…
A light stop, with an R-parity-violating coupling $\lambda'_{131}$, has been suggested as an explanation of the excess in high-$Q^2$ neutral current events observed at the HERA collider. We show that in this scheme a corresponding excess in…
In the framework of the minimal supersymmetric standard model with an R-parity breaking coupling of the scalar top quark (stop) we investigate production processes and decay properties of the stop at HERA energies. The model is…
In the framework of the minimal supersymmetric standard model (MSSM) and the R-parity breaking model (RBM), we investigate production processes of the scalar top (stop) at HERA energies. These models are characterized by the possible…
A search for scalar top quarks in R-parity violating supersymmetry is performed in e^+ p collisions at HERA using the H1 detector. The data, taken at sqrt{s}=319 GeV and 301 GeV, correspond to an integrated luminosity of 106 pb^-1. The…
We explore interpretations of the anomaly observed by H1 and ZEUS at HERA in deep-inelastic e^+ p scattering at very large Q^2. We discuss the possibilities of new effective interactions and the production of a narrow state of mass 200 GeV…
The excess of high Q^2 events at HERA has been the subject of recent extensive studies in the framework of several models related to new physics. Here, we would like to concentrate on the most promising, from our point of view, model…