Search for heavy Majorana neutrinos with the ATLAS detector in pp collisions at $\sqrt{s} = 8$ TeV

Understand

A search for heavy Majorana neutrinos in events containing a pair of high-$p_{\mathrm{T}}$ leptons of the same charge and high-$p_{\mathrm{T}}$ jets is presented.

• The search uses $20.3 \mathrm{fb}^{-1}$ of $pp$ collision data collected with the ATLAS detector at the CERN Large Hadron Collider with a centre-of-mass energy of $\sqrt{s} = 8$ TeV.
• The data are found to be consistent with the background-only hypothesis based on the Standard Model expectation.
• In the context of a Type-I seesaw mechanism, limits are set on the production cross-section times branching ratio for production of heavy Majorana neutrinos in the mass range between 100 and 500 GeV.