Reinterpretation of ATLAS and CMS searches in monojet and mono-$V$ final states: prospects of limits on excited neutrinos
Searches for final states with large missing transverse momentum recoiling against a jet or a hadronically decaying vector boson provide strong constraints on a wide class of physics scenarios beyond the Standard Model. In this work, we reinterpret existing ATLAS and CMS monojet and mono-$V$ searches at $\sqrt{s} =$ 13 TeV in the context of excited-neutrino production. Published signal-region selections, post-fit background estimates, and observed event yields are used with simulated excited-neutrino signals to derive upper limits on the production cross-section as a function of the excited-neutrino mass. The monojet searches allow excited-neutrino masses of up to approximately 4 TeV to be excluded for representative benchmark scenarios. Mono-$V$ searches provide constraints on the parameter space region with large couplings to the SM electroweak gauge bosons and low excited-neutrino masses compared to the compositeness scale. This is complementary to the region probed by the monojet searches.