Search for charginos, neutralinos and gravitinos in e(+)e(-) interactions at root s = 183 GeV

An update of the searches for charginos and neutralinos is presented, based on a data sample corresponding to the 53.9 pb(-1) recorded by the DELPHI detector in 1997, at a centre-of-mass energy of 183 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 172 GeV. The (mu M-2) domain excluded by combining the neutralino and chargino searches implies a limit on the mass of the Lightest neutralino which, for a heavy sneutrino, is constrained to be above 29.1 GeV/c(2) for tan beta greater than or equal to 1. (C) 1999 Elsevier Science B.V. All rights reserved.