Related papers: Recognizing Superpartners at LEP
In the final run in the year 2000 the four experiments at the electron positron collider LEP have accumulated data corresponding to an integrated luminosity of more than 210 pb-1 per experiment at centre-of-mass energies up to 208 GeV.…
We apply a model-independent, agnostic approach to the collider phenomenology of supersymmetry (SUSY), in which all mass parameters are taken as free inputs at the weak scale. We consider the gauginos, higgsinos, and the first two…
We present a search for chargino and neutralino supersymmetric particles yielding same signed dilepton final states including one hadronically decaying tau lepton using 6.0 $fb^{-1}$ of data collected by the the CDF II detector. This…
Relatively light sneutrinos, which are experimentally allowed, may significantly affect the currently popular search strategies for supersymmetric particles by decaying dominantly into an invisible channel. In certain cases the second…
We use the three lepton and missing energy "trilepton" signature to search for chargino-neutralino production with $2.0 fb^{-1}$ of integrated luminosity collected by the CDF II experiment at the Tevatron $p\bar{p}$ collider. We expect…
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…
In the scenario recently proposed by Arkani-Hamed and Dimopoulos, the supersymmetric scalar particles are all very heavy, at least of the order of $10^9$ GeV but the gauginos, higgsino, and one of the CP-even neutral Higgs bosons remain…
Within the framework of supersymmetry, charginos and/or neutralinos are often the preferred topics of searches for experimental evidence. This is due to the facts that in much of parameter space they are the lightest supersymmetric partners…
The large amount of data accumulated at LEP2 by the ALEPH experiment has been used to search for supersymmetric particles. No signal has been found therefore limits have been determined. Within the Constrained Minimal Supersymmetric…
We investigate signatures induced by a very light pseudoscalar Higgs in neutralino decays in the Next-to-Minimal Supersymmetric Standard Model (NMSSM) and determine their observability at the LHC. We concentrate on scenarios which feature…
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…
We illustrate the sensitivities of LEP experiments to leptonic signals associated to models where supersymmetry (SUSY) is realized with spontaneous breaking of R-parity. We focus on missing transverse momentum plus acoplanar muon events…
In most supersymmetric theories, charginos $\tilde{\chi}^\pm_{1,2}$ belong to the class of the lightest supersymmetric particles and they are easy to observe at e^+e^- colliders. By measuring the total cross sections and the left-right…
We study the $e^{\pm}\mu^{\mp} + E^{miss}_T$ and $l^+l^- + E^{miss}_T$ signatures $(l = e, \mu)$ for different values of $\tan\beta$ in the mSUGRA model. With $\tan\beta$ rising, we observe a characteristic change in the shape of dilepton…
The gaugino mass relations $m_3/{g_3^2} = m_2/{g_2^2} = m_1/{g_1^2}$ are considered to be robust signals for supersymmetric grand unification. In this letter, we point out that these relations may be significantly modified in an interesting…
There is strong theoretical motivation for the study of events with 2 same-sign leptons, jets, and missing transverse energy (MET) at the Large Hadron Collider (LHC). There are many compelling models, for instance, supersymmetry and extra…
In view of the latest LEP data we consider the effects of charginos and neutralinos on the two-photon and bbbar signatures of the Higgs at the LHC. Assuming the usual GUT inspired relation between M_1 and M_2 we show that there are only…
If the sneutrino mass is below the chargino mass, the dominant decay mode of the lightest chargino is via a two-body decay channel $\chi^{\pm}_1 \ra \tilde{\nu} + l^{\pm}$. Sneutrinos are invisible in $R$-parity conserving supersymmetric…
The four LEP collaborations have performed searches for supersymmetric particles in light gravitino scenarios, when neutralinos and sleptons are produced and may present measurable decay lengths. The highest energy data has been analysed…
I explore the phenomenology of Supersymmetry models in which the gauginos are much heavier then that scalar particles of the MSSM. In these models, the gauginos are inaccessible to colliders while the scalar spectrum is compressed. I give…