Search for Right-Handed W Bosons and Heavy W^prime in pbar p Collisions at sqrt{s} =1.8 TeV

We report on a search for right-handed $W$ bosons ($W_R$). We used data collected with the D{\O} detector at the Fermilab Tevatron $p\bar p$ collider at $\sqrt{s}=$1.8 TeV to search for $W_R$ decays into an electron and a massive right-handed neutrino $W_R^\pm \to e^\pm N_R$. Using the inclusive electron data, we set mass limits independent of the $N_R$ decay: $m_{W_R}>650$ GeV/c$^2$ and $m_{W_R}>720$ GeV/c$^2$ at the 95% confidence level, valid for $m_{N_R}<{1/2}m_{W_R}$ and $m_{N_R} \ll m_{W_R}$ respectively. The latter also represents a new lower limit on the mass of a heavy left-handed $W$ boson ($W^\prime$) decaying into $e \nu$. In addition, limits on $m_{W_R}$ valid for larger values of the $N_R$ mass are obtained assuming that $N_R$ decays to an electron and two jets.