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Related papers: Recognizing Superpartners at LEP

200 papers

In a class of supersymmetric models with R-parity breaking the lightest stop can have new decay modes into third generation fermions, $\tilde{t}_1 \rightarrow b + \tau$. We show that this decay may be dominant or at least comparable to the…

High Energy Physics - Phenomenology · Physics 2009-09-17 A. Bartl , W. Porod , M. A. Garcia-Jareno , M. B. Magro , J. W. F. Valle , W. Majerotto

In this talk, as requested, I begin with a overview and with some basic reminders about how evidence for supersymmetry in nature might appear -- in particular, how SUSY signatures are never clear so it is difficult to search for them…

High Energy Physics - Phenomenology · Physics 2009-10-30 Gordon L. Kane

Single- and multi-photon events with missing energy are selected in 619/pb of data collected by the L3 detector at LEP at centre-of-mass energies between 189GeV and 209GeV. The cross sections of the process e^+e^- -> nu nu gamma (gamma) are…

High Energy Physics - Experiment · Physics 2012-08-27 L3 Collaboration

A search for charginos and neutralinos, predicted by supersymmetric theories, has been performed using a data sample of 57 pb-1 at centre-of-mass energies of 181-184 GeV taken with the OPAL detector at LEP. No evidence for chargino or…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL Collaboration , G. Abbiendi et al

We study the impact of present and future $(g-2)_\mu$ measurements on supersymmetric models. The corrections to $(g-2)_\mu$ become particularly relevant in the presence of light sleptons, charginos and neutralinos, especially in the large…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Carena , G. F. Giudice , C. E. M. Wagner

We show that LEPII will either discover charginos and neutralinos, or enable a very stringent upper limit to be placed on $\tan \beta$ as a function of the gluino mass. The only assumption we make is the existence of some unified model…

High Energy Physics - Phenomenology · Physics 2016-09-01 Marco A. Diaz , Steve F. King

In models with gravitino as the lightest supersymmetric particle(LSP), the next to lightest supersymmetric particle (NLSP) can have a long lifetime and appear stable in collider experiments. We study the leptonic signatures of such a…

High Energy Physics - Phenomenology · Physics 2010-11-03 Terrance Figy , Krzysztof Rolbiecki , Yudi Santoso

In the framework of gauge-mediated supersymmetry breaking models pair production of the lightest neutralinos, scalar leptons, or charginos at LEPII gives rise to interesting signals involving multilepton final states and missing energy. In…

High Energy Physics - Phenomenology · Physics 2009-10-30 Kingman Cheung , Duane A. Dicus , B. Dutta , S. Nandi

During the LEP2 operation, the 4 LEP experiments have collected data at centre-of-mass energies up to 209 GeV. Those data have been analysed in the search of charginos, neutralinos and sfermions in the framework of the Minimal…

High Energy Physics - Experiment · Physics 2007-05-23 T. Alderweireld

Supersymmetric models with a small neutralino-chargino mass difference, and as a result metastable charginos, have been a popular topic of investigation in collider phenomenology, e.g. in anomaly-mediated models of supersymmetry breaking.…

High Energy Physics - Phenomenology · Physics 2015-06-17 N. -E. Bomark , A. Kvellestad , S. Lola , P. Osland , A. R. Raklev

Charginos $\tilde{\chi}^\pm$ and neutralinos $\tilde{\chi}^0$ in supersymmetric theories can be produced copiously at $e^+e^-$ colliders and their properties can be measured with high accuracy. Consecutively to the chargino system, in which…

High Energy Physics - Phenomenology · Physics 2011-09-13 S. Y. Choi , J. Kalinowski , G. Moortgat-Pick , P. M. Zerwas

We study the production of neutralinos and charginos at LEP and at a linear collider in the case of spontaneously broken R-parity. We first investigate the constraints on the single neutralino and chargino production from the LEP 1…

High Energy Physics - Phenomenology · Physics 2011-09-13 K. Huitu , J. Maalampi , K. Puolamaki

The search for supersymmetry at Run 1 of LHC has resulted in gluino mass limits m(gluino)>~ 1.3 TeV for the case where m(gluino)<<m(squark) and in models with gaugino mass unification. The increased energy and ultimately luminosity of LHC13…

High Energy Physics - Phenomenology · Physics 2015-08-26 Baris Altunkaynak , Howard Baer , Vernon Barger , Peisi Huang

Among the possible decay modes of Higgs particles into supersymmetric states, neutralino and chargino decays play a prominent r\^ole. The experimental opportunities of observing such decay modes at LEP2 and at future e+e- linear colliders…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. Djouadi , P. Janot , J. Kalinowski , P. M. Zerwas

We propose an analysis of LEP constraints on radiative neutralino decays into a light gravitino, based on the plane of the Higgs mixing parameter mu and the SU(2) gaugino mass M_2. The preliminary LEP 2W constraints in the (mu, M_2) plane…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Ellis , J. Lopez , D. Nanopoulos

We consider a class of SUSY models in which the MSSM gauge group is supplemented with a gauged $U(1)_{B-L}$ symmetry and a global $U(1)_{R}$ symmetry. This extension introduces only electrically neutral states, and the new SUSY partners…

High Energy Physics - Phenomenology · Physics 2021-02-24 Waqas Ahmed , Shabbar Raza , Qaisar Shafi , Cem Salih Un , Bin Zhu

Previously, in the context of the minimal supersymmetric standard model (without {\em a priori} assumptions of parameter unification), we studied the constraints on weak-scale SUSY parameters from chargino production at LEP II, using as…

High Energy Physics - Phenomenology · Physics 2009-10-28 Jonathan L. Feng , Matthew J. Strassler

We study the Minimal Supersymmetric Standard Model (MSSM) with large gluino mass m_{\tilde{g}} >> 1 TeV. In particular, we discuss the LHC supersymmetry discovery signatures with n leptons + jets + E^{miss}_T, n >= 0 for the MSSM with large…

High Energy Physics - Phenomenology · Physics 2010-04-21 Yu. M. Andreev , N. V. Krasnikov , A. N. Toropin

We explore and contrast the single-photon and diphoton signals expected at LEP 2, that arise from neutralino-gravitino (e^+ e^- -> chi + gravitino -> gamma + E_miss) and neutralino-neutralino (e^+ e^- -> chi + chi -> gamma + gamma + E_miss)…

High Energy Physics - Phenomenology · Physics 2009-08-25 J. Lopez , D. Nanopoulos , A. Zichichi

We investigate squark and gluino pair production at LHC (CMS) with subsequent decays into quarks, leptons and LSP in models with effective supersymmetry where third generation of squarks is relatively light while the first two generations…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. I. Bityukov , N. V. Krasnikov