Search for Heavy Neutrinos and $\mathrm {W}$ Bosons with Right-Handed Couplings in Proton-Proton Collisions at $\sqrt{s} = 8\,\text {TeV} $

A search for heavy, right-handed neutrinos, $\mathrm {N}_{\ell }$ ( $\ell = \mathrm {e}, \mu$ ), and right-handed $\mathrm {W}_{\mathrm {R}}$ bosons, which arise in the left-right symmetric extensions of the standard model, has been performed by the CMS experiment. The search was based on a sample of two lepton plus two jet events collected in proton–proton collisions at a center-of-mass energy of 8 $\,\text {TeV}$ corresponding to an integrated luminosity of 19.7  $\mathrm{fb}^{-1}$ . For models with strict left-right symmetry, and assuming only one $\mathrm {N}_{\ell }$ flavor contributes significantly to the $\mathrm {W}_{\mathrm {R}}$ decay width, the region in the two-dimensional $(M_{\mathrm {W\mathrm {R}}}, M_{\mathrm {N\ell }})$ mass plane excluded at a 95 % confidence level extends to approximately $M_{\mathrm {W\mathrm {R}}} = 3.0\,\text {TeV}$ and covers a large range of neutrino masses below the $\mathrm {W}_{\mathrm {R}}$ boson mass, depending on the value of $M_{\mathrm {W\mathrm {R}}}$ . This search significantly extends the $(M_{\mathrm {W\mathrm {R}}}, M_{\mathrm {N\ell }})$ exclusion region beyond previous results.