Article

Search for supersymmetry with gauge-mediated breaking in diphoton events at D0.

Joint Institute for Nuclear Research, Dubna, Russia.
Physical Review Letters (Impact Factor: 7.73). 03/2005; 94(4):041801. DOI: 10.1103/PhysRevLett.94.041801
Source: PubMed

ABSTRACT We report the results of a search for supersymmetry (SUSY) with gauge-mediated breaking in the missing transverse energy distribution of inclusive diphoton events using 263 pb(-1) of data collected by the D0 experiment at the Fermilab Tevatron Collider in 2002-2004. No excess is observed above the background expected from standard model processes, and lower limits on the masses of the lightest neutralino and chargino of about 108 and 195 GeV, respectively, are set at the 95% confidence level. These are the most stringent limits to date for models with gauge-mediated SUSY breaking with a short-lived neutralino as the next-to-lightest SUSY particle.

1 Bookmark
 · 
162 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The Run I results on the searches for new physics in photon final states were intriguing. The rare eeγγ≠ET candidate event and the measured event rate for the signature ℓ+γ+≠ET, which was 2.7 sigma above the Standard Model predictions, sparked signature-based searches in the γγ+X and ℓγ+X channels. With more data in Run II we should be able to answer a simple question: was it an anomaly or were the Run I results the first evidence for new physics? We present searches for new physics in photon final states at CDF Run II, Fermilab, with substantially more data and a higher p̄p collision energy, 1.96TeV, and the upgraded CDF-II detector.
    European Physical Journal C 07/2006; 46:21-31. · 5.25 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Recent theoretical developments have shown that gauge mediation has a much larger parameter space of possible spectra and mixings than previously considered. Motivated by this, we explore the collider phenomenology of gauge mediation models where a general neutralino is the lightest MSSM superpartner (the NLSP), focusing on the potential reach from existing and future Tevatron searches. Promptly decaying general neutralino NLSPs can give rise to final states involving missing energy plus photons, Zs, Ws and/or Higgses. We survey the final states and determine those where the Tevatron should have the most sensitivity. We then estimate the reach of existing Tevatron searches in these final states and discuss new searches (or optimizations of existing ones) that should improve the reach. Finally we comment on the potential for discovery at the LHC. Comment: 41 pages, minor changes, added refs and discussion of previous literature
    Journal of High Energy Physics 11/2009; · 5.62 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present the first search for heavy, long-lived particles that decay to photons at a hadron collider. We use a sample of gamma + jet + missing transverse energy events in pp[over] collisions at square root[s] = 1.96 TeV taken with the CDF II detector. Candidate events are selected based on the arrival time of the photon at the detector. Using an integrated luminosity of 570 pb(-1) of collision data, we observe 2 events, consistent with the background estimate of 1.3+/-0.7 events. While our search strategy does not rely on model-specific dynamics, we set cross section limits in a supersymmetric model with [Formula: see text] and place the world-best 95% C.L. lower limit on the [Formula: see text] mass of 101 GeV/c(2) at [Formula: see text].
    Physical Review Letters 10/2007; 99(12):121801. · 7.73 Impact Factor

Full-text (2 Sources)

View
16 Downloads
Available from
Jun 6, 2014