  We report the first experimental demonstration of compensation of beam-beam
interaction effects in high-energy particle collider by using space-charge
forces of a low-energy electron beam. In our experiments, an electron lens, a
novel instrument developed for the beam-beam compensation, was set on a 980-GeV
proton bunch in the Tevatron proton-antiproton collider. The proton bunch
losses due to its interaction with antiproton beam were reduced by a factor of
2 when the electron lens was operating. We describe the principle of electron
lens operation and present experimental results.
