Searches for pair production of supersymmetric particles under the
assumption that R-parity is not conserved are presented, based on data
recorded by the DELPHI detector in 1998 from e(+)e(-) collisions at a
centre-of-mass energy of 189 GeV. Only one R-parity violating LL (E)
over bar term (i.e. one lambda coupling), which couples scalar leptons
to leptons, is considered to be dominant at a time. Moreover, it is
assumed that the strength of the R-parity violating couplings is such
that the lifetimes can be neglected. The search for pair production of
neutralinos, charginos and sleptons has been performed for both direct
R-parity violating decays and indirect cascade decays. The results are
in agreement with Standard Model expectations, and are used to update
the constraints on the MSSM parameter values and the mass limits
previously derived at root s = 183 GeV. The present 95% C.L. Limits on
supersymmetric particle masses are:
m(<(chi)over tilde>0) > 30 GeV/c(2) and m(<(chi)over tilde>+/-) > 94
GeV/c(2);
m(<(nu)over tilde>) > 76.5 GeV/c(2) (direct and indirect decays);
m((l) over tilde R) > 83 GeV/c(2) (indirect decay only).
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