Search for Heavy, Long-Lived Neutralinos that Decay to Photons at CDF II Using Photon Timing

Abstract

We present the results of the first hadron collider search for heavy, long-lived neutralinos that decay via lightest neutralino to gamma gravitino in gauge-mediated supersymmetry breaking models. Using an integrated luminosity of $570\pm 34p{b}^{-1}$ of $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV, we select $\gamma$+jet+missing transverse energy candidate events based on the arrival time of a high-energy photon at the electromagnetic calorimeter as measured with a timing system that was recently installed on the CDF II detector. We find 2 events, consistent with the background estimate of 1.3$\pm$0.7 events. While our search strategy does not rely on model-specific dynamics, we set cross section limits and place the world-best 95% C.L. lower limit on the neutralino mass of 101 GeV at lifetime = 5 ns.

Corrected author list

References in corpus (5)

• Discovering the Higgs Through Highly-Displaced Vertices
• First Run II Measurement of the W Boson Mass
• Search for Supersymmetry in Di-Photon Final States at sqrt{s} = 1.96 TeV
• The Timing System for the CDF Electromagnetic Calorimeters
• Search for Heavy, Long-Lived Particles that Decay to Photons at CDF II

Cited by in corpus (14)

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• Signal Processing for Pico-second Resolution Timing Measurements
• Search for Supersymmetry with Gauge-Mediated Breaking in Diphoton Events with Missing Transverse Energy at CDF II
• Search for Anomalous Production of Events with Two Photons and Additional Energetic Objects at CDF
• Revealing Randall-Sundrum Hidden Valleys
• A signature-based search for delayed photons in exclusive photon plus missing transverse energy events from $p\bar{p}$ collisions with $\sqrt{s}=1.96$ TeV
• Odd Decays from Even Anomalies: Gauge Mediation Signatures Without SUSY
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• Probing axino LSP from diphotons events with large missing transverse energy
• Searches for New Physics in Events with a photon and a missing energy at CDF Run II