  The KARMEN experiment at the spallation neutron source ISIS used \numub from
\mup--decay at rest in the search for neutrino oscillations \numubnueb in the
appearance mode, with p(\nueb,e+)n as detection reaction of \nueb. In total, 15
candidates fulfill all conditions for the \nueb signature, in agreement with
the background expectation of 15.8+-0.5 events, yielding no indication for
oscillations. A single event based likelihood analysis leads to upper limits on
the oscillation parameters: sin^2(2theta)<1.7x10e-3 for Dm^2>100 eV^2 and
Dm^2<0.055 eV^2 for sin^2(2theta)=1 at 90% confidence. Thus, KARMEN does not
confirm the LSND experiment and restricts significantly its favored parameter
region for \numubnueb.
