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arXiv · hep-ex/0104027

Search for charginos in e+e- interactions at sqrt(s) = 189 GeV

The DELPHI Collaboration·P. Abreu
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Abstract

An update of the searches for charginos and gravitinos is presented, based on a data sample corresponding to the 158 pb^{-1} recorded by the DELPHI detector in 1998, at a centre-of-mass energy of 189 GeV. No evidence for a signal was found. The lower mass limits are 4-5 GeV/c^2 higher than those obtained at a centre-of-mass energy of 183 GeV. The (μ,M_2) MSSM domain excluded by combining the chargino searches with neutralino searches at the Z resonance implies a limit on the mass of the lightest neutralino which, for a heavy sneutrino, is constrained to be above 31.0 GeV/c^2 for tan(beta) \geq 1.

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The DELPHI Collaboration, P. Abreu. 2001-04-13. Search for charginos in e+e- interactions at sqrt(s) = 189 GeV. https://doi.org/10.1016/s0370-2693(00)00313-0

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