Searches for prompt light gravitino signatures in e+ e- collisions at S**(1/2) = 189-GeV

Searches for final states expected in models with light gravitinos have been performed, including experimental topologies with multi-leptons with missing energy, leptons and photons with missing energy, and jets and photons with missing energy. No excess over the expectations from the Standard Model has been observed. Limits are placed on production cross-sections in the different experimental topologies. Additionally, combining with searches for the anomalous production of lepton and photon pairs with missing energy, results are interpreted in the context of minimal models of gauge mediated SUSY breaking. Exclusion limits at the 95% confidence level on the supersymmetric particle masses of m ℓ ̃ > 83 GeV and m χ ̃ 1 0 > 85 GeV for tan β =2, and m τ ̃ > 69 GeV, m e ̃ , μ ̃ > 88 GeV and m χ ̃ 1 0 > 76 GeV for tan β =20, are established.

Note:

19 pages, 6 figures, submitted to Phys. Lett. B Report-no: CERN-EP-2000-078

electron positron: colliding beams
electron positron: annihilation
new particle: search for
gravitino: LSP
supersymmetry: symmetry breaking
sparticle: mass
lower limit
sparticle: pair production
sparticle: decay
slepton

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Figures(0)

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