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

This Letter presents a search for direct production of charginos and neutralinos via electroweak interactions. The results are based on data from proton-proton collisions at a center-of-mass energy of 13 TeV collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb$^{-1}$. The search considers final states with large missing transverse momentum and pairs of hadronically decaying bosons WW, WZ, and WH, where H is the Higgs boson. These bos...

A search for stable and long-lived massive particles of electric charge |Q/e|=1 or fractional charges of 2/3, 4/3, and 5/3 is reported using data collected by the OPAL detector at LEP, at centre-of-mass energies from 130 to 209 GeV. These particles are assumed to be pair-produced in e+e- collisions and not to interact strongly. No evidence for the production of these particles was observed. Model-independent upper limits on the production cross-section between 0.005 and 0.028...

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. These data have been used to extend the search for supersymmetric particles in the new energy domain. In the present paper the results of searches for sfermions, charginos and neutralinos are described, assuming the minimal supersymmetric stand...

We have searched in $p \bar{p}$ collisions at $\sqrt{s}$ = 1.8 TeV for events with three charged leptons and missing transverse energy. In the Minimal Supersymmetric Standard Model, we expect trilepton events from chargino-neutralino ($\chione \chitwo$) pair production, with subsequent decay into leptons. We observe no candidate $e^+e^-e^\pm$, $e^+e^-\mu^\pm$, $e^\pm\mu^+\mu^-$ or $\mu^+\mu^-\mu^\pm$ events in 106 pb$^{-1}$ integrated luminosity. We present limits on the sum ...

A search for pair-production of supersymmetric particles under the assumption that R-parity is violated via a dominant LLE 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 is translated into lower limits on the mass of charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, charginos with masses less than ...

Supersymmetry is one of the most popular extensions of the Standard Model of particle physics, as it offers solutions to several shortcomings of the Standard Model. Natural supersymmetric models favor masses for the new particles which are predicted by supersymmetry in the range of hundreds of GeV, well within the reach of the Large Hadron Collider at CERN. If squarks and gluinos are much heavier, the production of charginos and neutralinos may be the dominant production mode...

I summarize a recent study by the GAMBIT Collaboration in which we investigated the combined collider constraints on the chargino and neutralino sector of the Minimal Supersymmetric Standard Model. Through a large fit using GAMBIT we found that current ATLAS and CMS results with 36 fb$^{-1}$ of 13 TeV LHC collision data do not provide a general constraint on the lightest neutralino and chargino masses. Further, we found that a pattern of excesses in some of the LHC analyses c...

We present the results of a search for associated production of the lightest chargino and next-to-lightest neutralino using 1 fb$^{-1}$ of $\sqrt s$ = 1.96 TeV p$\rm \bar p$ data collected with the CDF detector at the Tevatron. We combine the results of several multi-lepton final states to set upper limits on the cross section times branching ratio for chargino-neutralino production as a function of the chargino mass.

A search for neutral Higgs bosons has been performed with the OPAL detector at LEP, using approximately 170 pb-1 of e+e- collision data collected at sqrt(s)~189GeV. Searches have been performed for the Standard Model (SM) process e+e- to H0Z0 and the MSSM processes e+e- to H0Z0, A0h0. The searches are sensitive to the b b-bar and tau antitau decay modes of the Higgs bosons, and also to the MSSM decay mode h0 to A0A0. OPAL search results at lower centre-of-mass energies have b...

A search for pair produced scalar fermions with couplings that violate R-parity has been performed using a data sample corresponding to an integrated luminosity of 56 pb-1 at a centre-of-mass energy of sqrt{s}= 183 GeV collected with the OPAL detector at LEP. An important consequence of R-parity breaking interactions is that the lightest supersymmetric particle is expected to be unstable. Searches for R-parity violating decays of charged sleptons, sneutrinos and stop quarks h...