Search for Chargino and Neutralino Production at sqrt{s} = 170 and 172 GeV at LEP

DELPHI data collected at centre-of-mass energies up to 208 GeV have been analysed to search for charginos, neutralinos and sfermions in the framework of the Minimal Supersymmetric Standard Model (MSSM) with R-parity conservation. No evidence for a signal was found in any of the channels. The results of each search were used to derive limits on production cross-sections and particle masses. In addition, the combined result of all searches excludes regions in the parameter spac...

The data collected by the OPAL experiment at sqrts=183 GeV were used to search for Higgs bosons which are predicted by the Standard Model and various extensions, such as general models with two Higgs field doublets and the Minimal Supersymmetric Standard Model (MSSM). The data correspond to an integrated luminosity of approximately 54pb-1. None of the searches for neutral and charged Higgs bosons have revealed an excess of events beyond the expected background. This negative ...

A search for the direct production of charginos and neutralinos in final states with at least two hadronically decaying tau leptons is presented. The analysis uses a dataset of $pp$ collisions corresponding to an integrated luminosity of 36.1 fb$^{-1}$, recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV. No significant deviation from the Standard Model background expectation is observed. Limits are derived in scenarios of $\tild...

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 lambda''_ijk is non-negligible. No signal is found in data up to a centre-of-mass energy of 208GeV. Limits on the production cross sections and on the masses of supersymmetric particles are derived.

A search for stable and long-lived massive particles of electric charge |Q/e| = 1 or 2/3, pair-produced in e+e- collisions at centre-of-mass energies from 130 to 183 GeV, is reported by the OPAL collaboration at LEP. No evidence for production of these particles was observed in a mass range between 45 and 89.5 GeV. Model-independent upper limits on the production cross-section between 0.05 and 0.19 pb have been derived for scalar and spin-1/2 particles with charge +/-1. Withi...

Charginos are expected to be the lightest observable supersymmetric particles in many of the supersymmetric models. In the scenario that lighter charginios are pair-produced at CERN LEP II, we present a straightforward procedure for determining the SUSY parameters, $\tan\beta$, $M_2$, $\mu$, and the electron sneutrino mass $m_{\tilde{\nu}}$ up to a four-fold discrete ambiguity, although a large number of unknown SUSY parameters are involved in chargino decays.

The results from a search for chargino-neutralino or chargino pair production via electroweak interactions are summarized. The results are based on a sample of $\sqrt{s}=13~\mathrm{TeV}$ proton-proton collisions from the LHC, recorded with the CMS detector~\cite{cms} and corresponding to an integrated luminosity of $137~\mathrm{fb}^{-1}$. The search considers final states with large missing transverse momentum and pairs of hadronically decaying bosons WW, WZ, and WH, which ar...

A search for pair-production of supersymmetric particles under the assumption that R-parity is violated via a dominant LQDbar coupling has been performed using the data collected by ALEPH at centre-of-mass energies of 130-172 GeV. The observed candidate events in the data are in agreement with the Standard Model expectation. This result is translated into lower limits on the masses of charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, for m_0=500 GeV/c^2 ...

Three searches for the direct production of staus or charginos and neutralinos in final states with at least two hadronically decaying $\tau$-leptons are presented. For chargino and neutralino production, decays via intermediate staus or $W$ and $h$ bosons are considered. The analysis uses a dataset of $pp$ collisions corresponding to an integrated luminosity of 139 $fb^{-1}$, recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV. ...

We present the current status of searches for supersymmetry performed at the Tevatron accelerator at Fermilab by the CDF and D0 collaborations using luminosity of up to 2.1 fb-1. We focus on searches for charginos, neutralinos, squarks, gluinos and sneutrinos in several supersymmetric scenarios. No supersymmetric signal is detected and limits on the masses and production cross sections for the supersymmetric particles are set.