Search for chargino-neutralino pair production with the D0 detector at the Tevatron

We have searched for evidence for the chargino (bar χ)1± and neutralino ((bar χ)20) pair production in proton anti-proton collisions at a center of mass energy of 1.96 TeV with the D0 detector at the Fermilab Tevatron Collider. Data corresponding to an integrated luminosity of 124.5 pb-1 were examined for events containing like-sign electron pair and missing energy for the first time at D0. They observed no excess above the yield from Standard Model processes. In the framework of mSUGRA, they set a series of upper limits, at the 95% confidence level, of the chargino neutralino production cross section times the branching fraction to tri-electrons as a function of the chargino mass. These limits range from 0.79 pb for mbarχ)1±) = 86.9 GeV/c2 to 0.52 pb for mbarχ)1±) = 115.1 GeV/c2